Hi, In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common) Regards Michael
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places)
Regards Michael _______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places)
+1 NGuid IIRC was introduced for nullable GUID (i.e - Integer vs int ) I guess this was created back at the porting days, and now we don't need it, as non primitives can always be nullable.
Regards Michael _______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
_______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places)
Hi, And for the new people out here... why not kill both and use plain standard java UUID[1]? I think we should kill compat, I don't see any value in fixing anything about it while leaving it intact. Regards, Alon Bar-Lev. [1] http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places) Hi,
And for the new people out here... why not kill both and use plain standard java UUID[1]?
+1 for using java.util.UUID NGuid functionality that should be extracted during the refactor is - 1. refactor DB and Java so empty or null return values are null and not EMPTY_GUID 2. the special constructor of NGuid for UUID return by Microsoft AD should be extracted to a factory/utility
I think we should kill compat, I don't see any value in fixing anything about it while leaving it intact.
Regards, Alon Bar-Lev.
[1] http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html _______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
----- Original Message -----
From: "Roy Golan" <rgolan@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 9:18:21 AM Subject: Re: [Engine-devel] Guid & NGuid
On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places) Hi,
And for the new people out here... why not kill both and use plain standard java UUID[1]?
+1 for using java.util.UUID
NGuid functionality that should be extracted during the refactor is - 1. refactor DB and Java so empty or null return values are null and not EMPTY_GUID 2. the special constructor of NGuid for UUID return by Microsoft AD should be extracted to a factory/utility
I think we should kill compat, I don't see any value in fixing anything about it while leaving it intact.
Regards, Alon Bar-Lev.
[1] http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html Actually there is exists one reason not to use directly UUID at server side. The main operations on Guid today it is to convert object to Guid or Guid to string. Guid it is immutable object, number of Guids is limited and almost never changed, These sound like classical case for object that can be cached. Benefit - reduced number of string manipulations, reduced number of created instances, less work for garbage collection
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 9:47:29 AM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Roy Golan" <rgolan@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 9:18:21 AM Subject: Re: [Engine-devel] Guid & NGuid
On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places) Hi,
And for the new people out here... why not kill both and use plain standard java UUID[1]?
+1 for using java.util.UUID
NGuid functionality that should be extracted during the refactor is - 1. refactor DB and Java so empty or null return values are null and not EMPTY_GUID 2. the special constructor of NGuid for UUID return by Microsoft AD should be extracted to a factory/utility
I think we should kill compat, I don't see any value in fixing anything about it while leaving it intact.
Regards, Alon Bar-Lev.
[1] http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html Actually there is exists one reason not to use directly UUID at server side. The main operations on Guid today it is to convert object to Guid or Guid to string. Guid it is immutable object, number of Guids is limited and almost never changed, These sound like classical case for object that can be cached. Benefit - reduced number of string manipulations, reduced number of created instances, less work for garbage collection Ok, but this functionality does not exist (yet :) )
_______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 8:47:29 AM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Roy Golan" <rgolan@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 9:18:21 AM Subject: Re: [Engine-devel] Guid & NGuid
On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places) Hi,
And for the new people out here... why not kill both and use plain standard java UUID[1]?
+1 for using java.util.UUID
NGuid functionality that should be extracted during the refactor is - 1. refactor DB and Java so empty or null return values are null and not EMPTY_GUID 2. the special constructor of NGuid for UUID return by Microsoft AD should be extracted to a factory/utility
I think we should kill compat, I don't see any value in fixing anything about it while leaving it intact.
Regards, Alon Bar-Lev.
[1] http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html Actually there is exists one reason not to use directly UUID at server side. The main operations on Guid today it is to convert object to Guid or Guid to string. Guid it is immutable object, number of Guids is limited and almost never changed, These sound like classical case for object that can be cached. Benefit - reduced number of string manipulations, reduced number of created instances, less work for garbage collection
UUID has the same properties, it is immutable. So you could do the same with UUID, but I am not sure you could effectively cache these objects and prove that you are saving either CPU, heap, or GC time.
_______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
----- Original Message ----- > From: "Laszlo Hornyak" <lhornyak@redhat.com> > To: "Michael Kublin" <mkublin@redhat.com> > Cc: engine-devel@ovirt.org > Sent: Monday, February 4, 2013 9:56:28 AM > Subject: Re: [Engine-devel] Guid & NGuid > > > > ----- Original Message ----- > > From: "Michael Kublin" <mkublin@redhat.com> > > To: engine-devel@ovirt.org > > Sent: Monday, February 4, 2013 8:47:29 AM > > Subject: Re: [Engine-devel] Guid & NGuid > > > > > > > > ----- Original Message ----- > > > From: "Roy Golan" <rgolan@redhat.com> > > > To: engine-devel@ovirt.org > > > Sent: Monday, February 4, 2013 9:18:21 AM > > > Subject: Re: [Engine-devel] Guid & NGuid > > > > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote: > > > > > > > > ----- Original Message ----- > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com> > > > >> To: "Michael Kublin" <mkublin@redhat.com> > > > >> Cc: "engine-devel" <engine-devel@ovirt.org> > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM > > > >> Subject: Re: [Engine-devel] Guid & NGuid > > > >> > > > >> > > > >> > > > >> ----- Original Message ----- > > > >>> From: "Michael Kublin" <mkublin@redhat.com> > > > >>> To: "engine-devel" <engine-devel@ovirt.org> > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM > > > >>> Subject: [Engine-devel] Guid & NGuid > > > >>> > > > >>> Hi, > > > >>> > > > >>> In ovirt-engine code we have Guid and NGuid objects. > > > >>> Guid is extends NGuid and also NGuid class has method > > > >>> getValue() > > > >>> which should return Guid. > > > >>> As for me these two classes are look like the same and I > > > >>> don't > > > >>> see > > > >>> to > > > >>> much differences between them. > > > >>> My proposal is to remove NGuid and move it functionality to > > > >>> Guid > > > >>> (Because of Guid is much more common) > > > >>> > > > >> i agree, but we need to take another step forward and allow > > > >> Guid > > > >> to > > > >> be null (as it should) > > > >> and not assume its EMPTY or have a value (i'm pretty sure we > > > >> have > > > >> this assumption in many places) > > > > Hi, > > > > > > > > And for the new people out here... why not kill both and use > > > > plain > > > > standard java UUID[1]? > > > +1 for using java.util.UUID > > > > > > NGuid functionality that should be extracted during the refactor > > > is > > > - > > > 1. refactor DB and Java so empty or null return values are null > > > and > > > not > > > EMPTY_GUID > > > 2. the special constructor of NGuid for UUID return by Microsoft > > > AD > > > should be extracted to a factory/utility > > > > I think we should kill compat, I don't see any value in fixing > > > > anything about it while leaving it intact. > > > > > > > > Regards, > > > > Alon Bar-Lev. > > > > > > > > [1] > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html > > Actually there is exists one reason not to use directly UUID at > > server side. > > The main operations on Guid today it is to convert object to Guid > > or > > Guid to string. > > Guid it is immutable object, number of Guids is limited and almost > > never changed, > > These sound like classical case for object that can be cached. > > Benefit - reduced number of string manipulations, reduced number of > > created instances, less work > > for garbage collection > > UUID has the same properties, it is immutable. So you could do the > same with UUID, but I am not sure you could effectively cache these > objects and prove that you are saving either CPU, heap, or GC time. These is a very common pattern: 1) implementation of valueOf() for most classes like Integer, Double, etc... has some kind of cache. 2) JVM has cache for strings that can be used and that cache can be tweaked by some JVM opts. 3) Most of our operations is perform query on DB, send request to host or parse response from host and Guid is very common object that is immutable. I am agree that these will not solve all our performance problems but can provide some benefit, especially when it is very easy to implement.
----- Original Message -----
>
>
> ----- Original Message -----
> > From: "Laszlo Hornyak" <lhornyak@redhat.com>
> > To: "Michael Kublin" <mkublin@redhat.com>
> > Cc: engine-devel@ovirt.org
> > Sent: Monday, February 4, 2013 9:56:28 AM
> > Subject: Re: [Engine-devel] Guid & NGuid
> >
> >
> >
> > ----- Original Message -----
> > > From: "Michael Kublin" <mkublin@redhat.com>
> > > To: engine-devel@ovirt.org
> > > Sent: Monday, February 4, 2013 8:47:29 AM
> > > Subject: Re: [Engine-devel] Guid & NGuid
> > >
> > >
> > >
> > > ----- Original Message -----
> > > > From: "Roy Golan" <rgolan@redhat.com>
> > > > To: engine-devel@ovirt.org
> > > > Sent: Monday, February 4, 2013 9:18:21 AM
> > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > >
> > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
> > > > >
> > > > > ----- Original Message -----
> > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com>
> > > > >> To: "Michael Kublin" <mkublin@redhat.com>
> > > > >> Cc: "engine-devel" <engine-devel@ovirt.org>
> > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM
> > > > >> Subject: Re: [Engine-devel] Guid & NGuid
> > > > >>
> > > > >>
> > > > >>
> > > > >> ----- Original Message -----
> > > > >>> From: "Michael Kublin" <mkublin@redhat.com>
> > > > >>> To: "engine-devel" <engine-devel@ovirt.org>
> > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM
> > > > >>> Subject: [Engine-devel] Guid & NGuid
> > > > >>>
> > > > >>> Hi,
> > > > >>>
> > > > >>> In ovirt-engine code we have Guid and NGuid objects.
> > > > >>> Guid is extends NGuid and also NGuid class has method
> > > > >>> getValue()
> > > > >>> which should return Guid.
> > > > >>> As for me these two classes are look like the same and I
> > > > >>> don't
> > > > >>> see
> > > > >>> to
> > > > >>> much differences between them.
> > > > >>> My proposal is to remove NGuid and move it functionality to
> > > > >>> Guid
> > > > >>> (Because of Guid is much more common)
> > > > >>>
> > > > >> i agree, but we need to take another step forward and allow
> > > > >> Guid
> > > > >> to
> > > > >> be null (as it should)
> > > > >> and not assume its EMPTY or have a value (i'm pretty sure we
> > > > >> have
> > > > >> this assumption in many places)
> > > > > Hi,
> > > > >
> > > > > And for the new people out here... why not kill both and use
> > > > > plain
> > > > > standard java UUID[1]?
> > > > +1 for using java.util.UUID
> > > >
> > > > NGuid functionality that should be extracted during the
> > > > refactor
> > > > is
> > > > -
> > > > 1. refactor DB and Java so empty or null return values are null
> > > > and
> > > > not
> > > > EMPTY_GUID
> > > > 2. the special constructor of NGuid for UUID return by
> > > > Microsoft
> > > > AD
> > > > should be extracted to a factory/utility
> > > > > I think we should kill compat, I don't see any value in
> > > > > fixing
> > > > > anything about it while leaving it intact.
> > > > >
> > > > > Regards,
> > > > > Alon Bar-Lev.
> > > > >
> > > > > [1]
> > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
> > > Actually there is exists one reason not to use directly UUID at
> > > server side.
> > > The main operations on Guid today it is to convert object to Guid
> > > or
> > > Guid to string.
> > > Guid it is immutable object, number of Guids is limited and
> > > almost
> > > never changed,
> > > These sound like classical case for object that can be cached.
> > > Benefit - reduced number of string manipulations, reduced number
> > > of
> > > created instances, less work
> > > for garbage collection
> >
> > UUID has the same properties, it is immutable. So you could do the
> > same with UUID, but I am not sure you could effectively cache these
> > objects and prove that you are saving either CPU, heap, or GC time.
> These is a very common pattern:
> 1) implementation of valueOf() for most classes like Integer, Double,
> etc... has some kind of cache.
> 2) JVM has cache for strings that can be used and that cache can be
> tweaked by some JVM opts.
> 3) Most of our operations is perform query on DB, send request to
> host or parse response from host and Guid
> is very common object that is immutable.
> I am agree that these will not solve all our performance problems but
> can provide some benefit, especially when it is very easy
> to implement.
We could still achieve that using a UUIDCreator class and call it instead of Guid.fromString("")..
Whether this is cached or not is another question which can be solved later and checked to see if the cache improves performance or not.
>
>
> _______________________________________________
> Engine-devel mailing list
> Engine-devel@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/engine-devel
>
----- Original Message -----
> From: "Mike Kolesnik" <mkolesni@redhat.com>
> To: "Michael Kublin" <mkublin@redhat.com>
> Cc: engine-devel@ovirt.org
> Sent: Monday, February 4, 2013 11:48:45 AM
> Subject: Re: [Engine-devel] Guid & NGuid
>
> ----- Original Message -----
> >
> >
> > ----- Original Message -----
> > > From: "Laszlo Hornyak" <lhornyak@redhat.com>
> > > To: "Michael Kublin" <mkublin@redhat.com>
> > > Cc: engine-devel@ovirt.org
> > > Sent: Monday, February 4, 2013 9:56:28 AM
> > > Subject: Re: [Engine-devel] Guid & NGuid
> > >
> > >
> > >
> > > ----- Original Message -----
> > > > From: "Michael Kublin" <mkublin@redhat.com>
> > > > To: engine-devel@ovirt.org
> > > > Sent: Monday, February 4, 2013 8:47:29 AM
> > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > >
> > > >
> > > >
> > > > ----- Original Message -----
> > > > > From: "Roy Golan" <rgolan@redhat.com>
> > > > > To: engine-devel@ovirt.org
> > > > > Sent: Monday, February 4, 2013 9:18:21 AM
> > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > >
> > > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
> > > > > >
> > > > > > ----- Original Message -----
> > > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com>
> > > > > >> To: "Michael Kublin" <mkublin@redhat.com>
> > > > > >> Cc: "engine-devel" <engine-devel@ovirt.org>
> > > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM
> > > > > >> Subject: Re: [Engine-devel] Guid & NGuid
> > > > > >>
> > > > > >>
> > > > > >>
> > > > > >> ----- Original Message -----
> > > > > >>> From: "Michael Kublin" <mkublin@redhat.com>
> > > > > >>> To: "engine-devel" <engine-devel@ovirt.org>
> > > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM
> > > > > >>> Subject: [Engine-devel] Guid & NGuid
> > > > > >>>
> > > > > >>> Hi,
> > > > > >>>
> > > > > >>> In ovirt-engine code we have Guid and NGuid objects.
> > > > > >>> Guid is extends NGuid and also NGuid class has method
> > > > > >>> getValue()
> > > > > >>> which should return Guid.
> > > > > >>> As for me these two classes are look like the same and I
> > > > > >>> don't
> > > > > >>> see
> > > > > >>> to
> > > > > >>> much differences between them.
> > > > > >>> My proposal is to remove NGuid and move it functionality
> > > > > >>> to
> > > > > >>> Guid
> > > > > >>> (Because of Guid is much more common)
> > > > > >>>
> > > > > >> i agree, but we need to take another step forward and
> > > > > >> allow
> > > > > >> Guid
> > > > > >> to
> > > > > >> be null (as it should)
> > > > > >> and not assume its EMPTY or have a value (i'm pretty sure
> > > > > >> we
> > > > > >> have
> > > > > >> this assumption in many places)
> > > > > > Hi,
> > > > > >
> > > > > > And for the new people out here... why not kill both and
> > > > > > use
> > > > > > plain
> > > > > > standard java UUID[1]?
> > > > > +1 for using java.util.UUID
> > > > >
> > > > > NGuid functionality that should be extracted during the
> > > > > refactor
> > > > > is
> > > > > -
> > > > > 1. refactor DB and Java so empty or null return values are
> > > > > null
> > > > > and
> > > > > not
> > > > > EMPTY_GUID
> > > > > 2. the special constructor of NGuid for UUID return by
> > > > > Microsoft
> > > > > AD
> > > > > should be extracted to a factory/utility
> > > > > > I think we should kill compat, I don't see any value in
> > > > > > fixing
> > > > > > anything about it while leaving it intact.
> > > > > >
> > > > > > Regards,
> > > > > > Alon Bar-Lev.
> > > > > >
> > > > > > [1]
> > > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
> > > > Actually there is exists one reason not to use directly UUID at
> > > > server side.
> > > > The main operations on Guid today it is to convert object to
> > > > Guid
> > > > or
> > > > Guid to string.
> > > > Guid it is immutable object, number of Guids is limited and
> > > > almost
> > > > never changed,
> > > > These sound like classical case for object that can be cached.
> > > > Benefit - reduced number of string manipulations, reduced
> > > > number
> > > > of
> > > > created instances, less work
> > > > for garbage collection
> > >
> > > UUID has the same properties, it is immutable. So you could do
> > > the
> > > same with UUID, but I am not sure you could effectively cache
> > > these
> > > objects and prove that you are saving either CPU, heap, or GC
> > > time.
> > These is a very common pattern:
> > 1) implementation of valueOf() for most classes like Integer,
> > Double,
> > etc... has some kind of cache.
> > 2) JVM has cache for strings that can be used and that cache can be
> > tweaked by some JVM opts.
> > 3) Most of our operations is perform query on DB, send request to
> > host or parse response from host and Guid
> > is very common object that is immutable.
> > I am agree that these will not solve all our performance problems
> > but
> > can provide some benefit, especially when it is very easy
> > to implement.
>
> We could still achieve that using a UUIDCreator class and call it
> instead of Guid.fromString("")..
>
> Whether this is cached or not is another question which can be solved
> later and checked to see if the cache improves performance or not.
These is already implementation, if it will be Guid.fromString("") or
UUIDCreator.
The issue is if we want to use cache, it should be implemented together
with deleting/replacing of Guid/NGuid , because of it much more easilly
----- Original Message -----
> From: "Michael Kublin" <mkublin@redhat.com>
> To: engine-devel@ovirt.org
> Sent: Monday, February 4, 2013 2:15:40 PM
> Subject: Re: [Engine-devel] Guid & NGuid
>
>
>
> ----- Original Message -----
> > From: "Mike Kolesnik" <mkolesni@redhat.com>
> > To: "Michael Kublin" <mkublin@redhat.com>
> > Cc: engine-devel@ovirt.org
> > Sent: Monday, February 4, 2013 11:48:45 AM
> > Subject: Re: [Engine-devel] Guid & NGuid
> >
> > ----- Original Message -----
> > >
> > >
> > > ----- Original Message -----
> > > > From: "Laszlo Hornyak" <lhornyak@redhat.com>
> > > > To: "Michael Kublin" <mkublin@redhat.com>
> > > > Cc: engine-devel@ovirt.org
> > > > Sent: Monday, February 4, 2013 9:56:28 AM
> > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > >
> > > >
> > > >
> > > > ----- Original Message -----
> > > > > From: "Michael Kublin" <mkublin@redhat.com>
> > > > > To: engine-devel@ovirt.org
> > > > > Sent: Monday, February 4, 2013 8:47:29 AM
> > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > >
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > > From: "Roy Golan" <rgolan@redhat.com>
> > > > > > To: engine-devel@ovirt.org
> > > > > > Sent: Monday, February 4, 2013 9:18:21 AM
> > > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > > >
> > > > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
> > > > > > >
> > > > > > > ----- Original Message -----
> > > > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com>
> > > > > > >> To: "Michael Kublin" <mkublin@redhat.com>
> > > > > > >> Cc: "engine-devel" <engine-devel@ovirt.org>
> > > > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM
> > > > > > >> Subject: Re: [Engine-devel] Guid & NGuid
> > > > > > >>
> > > > > > >>
> > > > > > >>
> > > > > > >> ----- Original Message -----
> > > > > > >>> From: "Michael Kublin" <mkublin@redhat.com>
> > > > > > >>> To: "engine-devel" <engine-devel@ovirt.org>
> > > > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM
> > > > > > >>> Subject: [Engine-devel] Guid & NGuid
> > > > > > >>>
> > > > > > >>> Hi,
> > > > > > >>>
> > > > > > >>> In ovirt-engine code we have Guid and NGuid objects.
> > > > > > >>> Guid is extends NGuid and also NGuid class has method
> > > > > > >>> getValue()
> > > > > > >>> which should return Guid.
> > > > > > >>> As for me these two classes are look like the same and
> > > > > > >>> I
> > > > > > >>> don't
> > > > > > >>> see
> > > > > > >>> to
> > > > > > >>> much differences between them.
> > > > > > >>> My proposal is to remove NGuid and move it
> > > > > > >>> functionality
> > > > > > >>> to
> > > > > > >>> Guid
> > > > > > >>> (Because of Guid is much more common)
> > > > > > >>>
> > > > > > >> i agree, but we need to take another step forward and
> > > > > > >> allow
> > > > > > >> Guid
> > > > > > >> to
> > > > > > >> be null (as it should)
> > > > > > >> and not assume its EMPTY or have a value (i'm pretty
> > > > > > >> sure
> > > > > > >> we
> > > > > > >> have
> > > > > > >> this assumption in many places)
> > > > > > > Hi,
> > > > > > >
> > > > > > > And for the new people out here... why not kill both and
> > > > > > > use
> > > > > > > plain
> > > > > > > standard java UUID[1]?
> > > > > > +1 for using java.util.UUID
> > > > > >
> > > > > > NGuid functionality that should be extracted during the
> > > > > > refactor
> > > > > > is
> > > > > > -
> > > > > > 1. refactor DB and Java so empty or null return values are
> > > > > > null
> > > > > > and
> > > > > > not
> > > > > > EMPTY_GUID
> > > > > > 2. the special constructor of NGuid for UUID return by
> > > > > > Microsoft
> > > > > > AD
> > > > > > should be extracted to a factory/utility
> > > > > > > I think we should kill compat, I don't see any value in
> > > > > > > fixing
> > > > > > > anything about it while leaving it intact.
> > > > > > >
> > > > > > > Regards,
> > > > > > > Alon Bar-Lev.
> > > > > > >
> > > > > > > [1]
> > > > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
> > > > > Actually there is exists one reason not to use directly UUID
> > > > > at
> > > > > server side.
> > > > > The main operations on Guid today it is to convert object to
> > > > > Guid
> > > > > or
> > > > > Guid to string.
> > > > > Guid it is immutable object, number of Guids is limited and
> > > > > almost
> > > > > never changed,
> > > > > These sound like classical case for object that can be
> > > > > cached.
> > > > > Benefit - reduced number of string manipulations, reduced
> > > > > number
> > > > > of
> > > > > created instances, less work
> > > > > for garbage collection
> > > >
> > > > UUID has the same properties, it is immutable. So you could do
> > > > the
> > > > same with UUID, but I am not sure you could effectively cache
> > > > these
> > > > objects and prove that you are saving either CPU, heap, or GC
> > > > time.
> > > These is a very common pattern:
> > > 1) implementation of valueOf() for most classes like Integer,
> > > Double,
> > > etc... has some kind of cache.
> > > 2) JVM has cache for strings that can be used and that cache can
> > > be
> > > tweaked by some JVM opts.
> > > 3) Most of our operations is perform query on DB, send request to
> > > host or parse response from host and Guid
> > > is very common object that is immutable.
> > > I am agree that these will not solve all our performance problems
> > > but
> > > can provide some benefit, especially when it is very easy
> > > to implement.
> >
> > We could still achieve that using a UUIDCreator class and call it
> > instead of Guid.fromString("")..
> >
> > Whether this is cached or not is another question which can be
> > solved
> > later and checked to see if the cache improves performance or not.
> These is already implementation, if it will be Guid.fromString("") or
> UUIDCreator.
> The issue is if we want to use cache, it should be implemented
> together
> with deleting/replacing of Guid/NGuid , because of it much more
> easilly
I think the value of using standard java classes is higher than the tuning of the engine at this regard. Dropping the compat thing is important activity.
After doing this conversion, use profiler to determine where major bottle necks are and fix these, I am not sure the above optimization will be first in list. If we invest resources in optimization better to invest in these that we suffer most.
Regards,
Alon
----- Original Message -----
> From: "Alon Bar-Lev" <alonbl@redhat.com>
> To: "Michael Kublin" <mkublin@redhat.com>
> Cc: engine-devel@ovirt.org
> Sent: Monday, February 4, 2013 4:17:39 PM
> Subject: Re: [Engine-devel] Guid & NGuid
>
>
>
> ----- Original Message -----
> > From: "Michael Kublin" <mkublin@redhat.com>
> > To: engine-devel@ovirt.org
> > Sent: Monday, February 4, 2013 2:15:40 PM
> > Subject: Re: [Engine-devel] Guid & NGuid
> >
> >
> >
> > ----- Original Message -----
> > > From: "Mike Kolesnik" <mkolesni@redhat.com>
> > > To: "Michael Kublin" <mkublin@redhat.com>
> > > Cc: engine-devel@ovirt.org
> > > Sent: Monday, February 4, 2013 11:48:45 AM
> > > Subject: Re: [Engine-devel] Guid & NGuid
> > >
> > > ----- Original Message -----
> > > >
> > > >
> > > > ----- Original Message -----
> > > > > From: "Laszlo Hornyak" <lhornyak@redhat.com>
> > > > > To: "Michael Kublin" <mkublin@redhat.com>
> > > > > Cc: engine-devel@ovirt.org
> > > > > Sent: Monday, February 4, 2013 9:56:28 AM
> > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > >
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > > From: "Michael Kublin" <mkublin@redhat.com>
> > > > > > To: engine-devel@ovirt.org
> > > > > > Sent: Monday, February 4, 2013 8:47:29 AM
> > > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > > >
> > > > > >
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > > From: "Roy Golan" <rgolan@redhat.com>
> > > > > > > To: engine-devel@ovirt.org
> > > > > > > Sent: Monday, February 4, 2013 9:18:21 AM
> > > > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > > > >
> > > > > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
> > > > > > > >
> > > > > > > > ----- Original Message -----
> > > > > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com>
> > > > > > > >> To: "Michael Kublin" <mkublin@redhat.com>
> > > > > > > >> Cc: "engine-devel" <engine-devel@ovirt.org>
> > > > > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM
> > > > > > > >> Subject: Re: [Engine-devel] Guid & NGuid
> > > > > > > >>
> > > > > > > >>
> > > > > > > >>
> > > > > > > >> ----- Original Message -----
> > > > > > > >>> From: "Michael Kublin" <mkublin@redhat.com>
> > > > > > > >>> To: "engine-devel" <engine-devel@ovirt.org>
> > > > > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM
> > > > > > > >>> Subject: [Engine-devel] Guid & NGuid
> > > > > > > >>>
> > > > > > > >>> Hi,
> > > > > > > >>>
> > > > > > > >>> In ovirt-engine code we have Guid and NGuid objects.
> > > > > > > >>> Guid is extends NGuid and also NGuid class has method
> > > > > > > >>> getValue()
> > > > > > > >>> which should return Guid.
> > > > > > > >>> As for me these two classes are look like the same
> > > > > > > >>> and
> > > > > > > >>> I
> > > > > > > >>> don't
> > > > > > > >>> see
> > > > > > > >>> to
> > > > > > > >>> much differences between them.
> > > > > > > >>> My proposal is to remove NGuid and move it
> > > > > > > >>> functionality
> > > > > > > >>> to
> > > > > > > >>> Guid
> > > > > > > >>> (Because of Guid is much more common)
> > > > > > > >>>
> > > > > > > >> i agree, but we need to take another step forward and
> > > > > > > >> allow
> > > > > > > >> Guid
> > > > > > > >> to
> > > > > > > >> be null (as it should)
> > > > > > > >> and not assume its EMPTY or have a value (i'm pretty
> > > > > > > >> sure
> > > > > > > >> we
> > > > > > > >> have
> > > > > > > >> this assumption in many places)
> > > > > > > > Hi,
> > > > > > > >
> > > > > > > > And for the new people out here... why not kill both
> > > > > > > > and
> > > > > > > > use
> > > > > > > > plain
> > > > > > > > standard java UUID[1]?
> > > > > > > +1 for using java.util.UUID
> > > > > > >
> > > > > > > NGuid functionality that should be extracted during the
> > > > > > > refactor
> > > > > > > is
> > > > > > > -
> > > > > > > 1. refactor DB and Java so empty or null return values
> > > > > > > are
> > > > > > > null
> > > > > > > and
> > > > > > > not
> > > > > > > EMPTY_GUID
> > > > > > > 2. the special constructor of NGuid for UUID return by
> > > > > > > Microsoft
> > > > > > > AD
> > > > > > > should be extracted to a factory/utility
> > > > > > > > I think we should kill compat, I don't see any value in
> > > > > > > > fixing
> > > > > > > > anything about it while leaving it intact.
> > > > > > > >
> > > > > > > > Regards,
> > > > > > > > Alon Bar-Lev.
> > > > > > > >
> > > > > > > > [1]
> > > > > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
> > > > > > Actually there is exists one reason not to use directly
> > > > > > UUID
> > > > > > at
> > > > > > server side.
> > > > > > The main operations on Guid today it is to convert object
> > > > > > to
> > > > > > Guid
> > > > > > or
> > > > > > Guid to string.
> > > > > > Guid it is immutable object, number of Guids is limited and
> > > > > > almost
> > > > > > never changed,
> > > > > > These sound like classical case for object that can be
> > > > > > cached.
> > > > > > Benefit - reduced number of string manipulations, reduced
> > > > > > number
> > > > > > of
> > > > > > created instances, less work
> > > > > > for garbage collection
> > > > >
> > > > > UUID has the same properties, it is immutable. So you could
> > > > > do
> > > > > the
> > > > > same with UUID, but I am not sure you could effectively cache
> > > > > these
> > > > > objects and prove that you are saving either CPU, heap, or GC
> > > > > time.
> > > > These is a very common pattern:
> > > > 1) implementation of valueOf() for most classes like Integer,
> > > > Double,
> > > > etc... has some kind of cache.
> > > > 2) JVM has cache for strings that can be used and that cache
> > > > can
> > > > be
> > > > tweaked by some JVM opts.
> > > > 3) Most of our operations is perform query on DB, send request
> > > > to
> > > > host or parse response from host and Guid
> > > > is very common object that is immutable.
> > > > I am agree that these will not solve all our performance
> > > > problems
> > > > but
> > > > can provide some benefit, especially when it is very easy
> > > > to implement.
> > >
> > > We could still achieve that using a UUIDCreator class and call it
> > > instead of Guid.fromString("")..
> > >
> > > Whether this is cached or not is another question which can be
> > > solved
> > > later and checked to see if the cache improves performance or
> > > not.
> > These is already implementation, if it will be Guid.fromString("")
> > or
> > UUIDCreator.
> > The issue is if we want to use cache, it should be implemented
> > together
> > with deleting/replacing of Guid/NGuid , because of it much more
> > easilly
>
> I think the value of using standard java classes is higher than the
> tuning of the engine at this regard. Dropping the compat thing is
> important activity.
Immutable object it is a common java design pattern
> After doing this conversion, use profiler to determine where major
Already was done, and already tested a cache solution (Simple POC solution took to implement less
than hour)
> bottle necks are and fix these, I am not sure the above optimization
> will be first in list.
Any optimization can not be first in the list, the best optimization is architecture change
> If we invest resources in optimization better
> to invest in these that we suffer most.
Most of the issues are well known.
>
> Regards,
> Alon
>
----- Original Message -----
> From: "Michael Kublin" <mkublin@redhat.com>
> To: "Alon Bar-Lev" <alonbl@redhat.com>
> Cc: engine-devel@ovirt.org
> Sent: Tuesday, February 5, 2013 9:28:26 AM
> Subject: Re: [Engine-devel] Guid & NGuid
>
>
>
> ----- Original Message -----
> > From: "Alon Bar-Lev" <alonbl@redhat.com>
> > To: "Michael Kublin" <mkublin@redhat.com>
> > Cc: engine-devel@ovirt.org
> > Sent: Monday, February 4, 2013 4:17:39 PM
> > Subject: Re: [Engine-devel] Guid & NGuid
> >
> >
> >
> > ----- Original Message -----
> > > From: "Michael Kublin" <mkublin@redhat.com>
> > > To: engine-devel@ovirt.org
> > > Sent: Monday, February 4, 2013 2:15:40 PM
> > > Subject: Re: [Engine-devel] Guid & NGuid
> > >
> > >
> > >
> > > ----- Original Message -----
> > > > From: "Mike Kolesnik" <mkolesni@redhat.com>
> > > > To: "Michael Kublin" <mkublin@redhat.com>
> > > > Cc: engine-devel@ovirt.org
> > > > Sent: Monday, February 4, 2013 11:48:45 AM
> > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > >
> > > > ----- Original Message -----
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > > From: "Laszlo Hornyak" <lhornyak@redhat.com>
> > > > > > To: "Michael Kublin" <mkublin@redhat.com>
> > > > > > Cc: engine-devel@ovirt.org
> > > > > > Sent: Monday, February 4, 2013 9:56:28 AM
> > > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > > >
> > > > > >
> > > > > >
> > > > > > ----- Original Message -----
> > > > > > > From: "Michael Kublin" <mkublin@redhat.com>
> > > > > > > To: engine-devel@ovirt.org
> > > > > > > Sent: Monday, February 4, 2013 8:47:29 AM
> > > > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > ----- Original Message -----
> > > > > > > > From: "Roy Golan" <rgolan@redhat.com>
> > > > > > > > To: engine-devel@ovirt.org
> > > > > > > > Sent: Monday, February 4, 2013 9:18:21 AM
> > > > > > > > Subject: Re: [Engine-devel] Guid & NGuid
> > > > > > > >
> > > > > > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
> > > > > > > > >
> > > > > > > > > ----- Original Message -----
> > > > > > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com>
> > > > > > > > >> To: "Michael Kublin" <mkublin@redhat.com>
> > > > > > > > >> Cc: "engine-devel" <engine-devel@ovirt.org>
> > > > > > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM
> > > > > > > > >> Subject: Re: [Engine-devel] Guid & NGuid
> > > > > > > > >>
> > > > > > > > >>
> > > > > > > > >>
> > > > > > > > >> ----- Original Message -----
> > > > > > > > >>> From: "Michael Kublin" <mkublin@redhat.com>
> > > > > > > > >>> To: "engine-devel" <engine-devel@ovirt.org>
> > > > > > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM
> > > > > > > > >>> Subject: [Engine-devel] Guid & NGuid
> > > > > > > > >>>
> > > > > > > > >>> Hi,
> > > > > > > > >>>
> > > > > > > > >>> In ovirt-engine code we have Guid and NGuid
> > > > > > > > >>> objects.
> > > > > > > > >>> Guid is extends NGuid and also NGuid class has
> > > > > > > > >>> method
> > > > > > > > >>> getValue()
> > > > > > > > >>> which should return Guid.
> > > > > > > > >>> As for me these two classes are look like the same
> > > > > > > > >>> and
> > > > > > > > >>> I
> > > > > > > > >>> don't
> > > > > > > > >>> see
> > > > > > > > >>> to
> > > > > > > > >>> much differences between them.
> > > > > > > > >>> My proposal is to remove NGuid and move it
> > > > > > > > >>> functionality
> > > > > > > > >>> to
> > > > > > > > >>> Guid
> > > > > > > > >>> (Because of Guid is much more common)
> > > > > > > > >>>
> > > > > > > > >> i agree, but we need to take another step forward
> > > > > > > > >> and
> > > > > > > > >> allow
> > > > > > > > >> Guid
> > > > > > > > >> to
> > > > > > > > >> be null (as it should)
> > > > > > > > >> and not assume its EMPTY or have a value (i'm pretty
> > > > > > > > >> sure
> > > > > > > > >> we
> > > > > > > > >> have
> > > > > > > > >> this assumption in many places)
> > > > > > > > > Hi,
> > > > > > > > >
> > > > > > > > > And for the new people out here... why not kill both
> > > > > > > > > and
> > > > > > > > > use
> > > > > > > > > plain
> > > > > > > > > standard java UUID[1]?
> > > > > > > > +1 for using java.util.UUID
> > > > > > > >
> > > > > > > > NGuid functionality that should be extracted during the
> > > > > > > > refactor
> > > > > > > > is
> > > > > > > > -
> > > > > > > > 1. refactor DB and Java so empty or null return values
> > > > > > > > are
> > > > > > > > null
> > > > > > > > and
> > > > > > > > not
> > > > > > > > EMPTY_GUID
> > > > > > > > 2. the special constructor of NGuid for UUID return by
> > > > > > > > Microsoft
> > > > > > > > AD
> > > > > > > > should be extracted to a factory/utility
> > > > > > > > > I think we should kill compat, I don't see any value
> > > > > > > > > in
> > > > > > > > > fixing
> > > > > > > > > anything about it while leaving it intact.
> > > > > > > > >
> > > > > > > > > Regards,
> > > > > > > > > Alon Bar-Lev.
> > > > > > > > >
> > > > > > > > > [1]
> > > > > > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html
> > > > > > > Actually there is exists one reason not to use directly
> > > > > > > UUID
> > > > > > > at
> > > > > > > server side.
> > > > > > > The main operations on Guid today it is to convert object
> > > > > > > to
> > > > > > > Guid
> > > > > > > or
> > > > > > > Guid to string.
> > > > > > > Guid it is immutable object, number of Guids is limited
> > > > > > > and
> > > > > > > almost
> > > > > > > never changed,
> > > > > > > These sound like classical case for object that can be
> > > > > > > cached.
> > > > > > > Benefit - reduced number of string manipulations, reduced
> > > > > > > number
> > > > > > > of
> > > > > > > created instances, less work
> > > > > > > for garbage collection
> > > > > >
> > > > > > UUID has the same properties, it is immutable. So you could
> > > > > > do
> > > > > > the
> > > > > > same with UUID, but I am not sure you could effectively
> > > > > > cache
> > > > > > these
> > > > > > objects and prove that you are saving either CPU, heap, or
> > > > > > GC
> > > > > > time.
> > > > > These is a very common pattern:
> > > > > 1) implementation of valueOf() for most classes like Integer,
> > > > > Double,
> > > > > etc... has some kind of cache.
> > > > > 2) JVM has cache for strings that can be used and that cache
> > > > > can
> > > > > be
> > > > > tweaked by some JVM opts.
> > > > > 3) Most of our operations is perform query on DB, send
> > > > > request
> > > > > to
> > > > > host or parse response from host and Guid
> > > > > is very common object that is immutable.
> > > > > I am agree that these will not solve all our performance
> > > > > problems
> > > > > but
> > > > > can provide some benefit, especially when it is very easy
> > > > > to implement.
> > > >
> > > > We could still achieve that using a UUIDCreator class and call
> > > > it
> > > > instead of Guid.fromString("")..
> > > >
> > > > Whether this is cached or not is another question which can be
> > > > solved
> > > > later and checked to see if the cache improves performance or
> > > > not.
> > > These is already implementation, if it will be
> > > Guid.fromString("")
> > > or
> > > UUIDCreator.
> > > The issue is if we want to use cache, it should be implemented
> > > together
> > > with deleting/replacing of Guid/NGuid , because of it much more
> > > easilly
> >
> > I think the value of using standard java classes is higher than the
> > tuning of the engine at this regard. Dropping the compat thing is
> > important activity.
> Immutable object it is a common java design pattern
> > After doing this conversion, use profiler to determine where major
> Already was done, and already tested a cache solution (Simple POC
> solution took to implement less
> than hour)
> > bottle necks are and fix these, I am not sure the above
> > optimization
> > will be first in list.
> Any optimization can not be first in the list, the best optimization
> is architecture change
> > If we invest resources in optimization better
> > to invest in these that we suffer most.
> Most of the issues are well known.
Please try to be less cryptic... Is this one of them?
>
> >
> > Regards,
> > Alon
> >
>
----- Original Message -----
From: "Alon Bar-Lev" <alonbl@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: engine-devel@ovirt.org Sent: Tuesday, February 5, 2013 9:29:20 AM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "Alon Bar-Lev" <alonbl@redhat.com> Cc: engine-devel@ovirt.org Sent: Tuesday, February 5, 2013 9:28:26 AM Subject: Re: [Engine-devel] Guid & NGuid
From: "Alon Bar-Lev" <alonbl@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: engine-devel@ovirt.org Sent: Monday, February 4, 2013 4:17:39 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 2:15:40 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Mike Kolesnik" <mkolesni@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: engine-devel@ovirt.org Sent: Monday, February 4, 2013 11:48:45 AM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
----- Original Message ----- > From: "Laszlo Hornyak" <lhornyak@redhat.com> > To: "Michael Kublin" <mkublin@redhat.com> > Cc: engine-devel@ovirt.org > Sent: Monday, February 4, 2013 9:56:28 AM > Subject: Re: [Engine-devel] Guid & NGuid > > > > ----- Original Message ----- > > From: "Michael Kublin" <mkublin@redhat.com> > > To: engine-devel@ovirt.org > > Sent: Monday, February 4, 2013 8:47:29 AM > > Subject: Re: [Engine-devel] Guid & NGuid > > > > > > > > ----- Original Message ----- > > > From: "Roy Golan" <rgolan@redhat.com> > > > To: engine-devel@ovirt.org > > > Sent: Monday, February 4, 2013 9:18:21 AM > > > Subject: Re: [Engine-devel] Guid & NGuid > > > > > > On 02/03/2013 03:19 PM, Alon Bar-Lev wrote: > > > > > > > > ----- Original Message ----- > > > >> From: "Omer Frenkel" <ofrenkel@redhat.com> > > > >> To: "Michael Kublin" <mkublin@redhat.com> > > > >> Cc: "engine-devel" <engine-devel@ovirt.org> > > > >> Sent: Sunday, February 3, 2013 3:12:19 PM > > > >> Subject: Re: [Engine-devel] Guid & NGuid > > > >> > > > >> > > > >> > > > >> ----- Original Message ----- > > > >>> From: "Michael Kublin" <mkublin@redhat.com> > > > >>> To: "engine-devel" <engine-devel@ovirt.org> > > > >>> Sent: Sunday, February 3, 2013 3:10:14 PM > > > >>> Subject: [Engine-devel] Guid & NGuid > > > >>> > > > >>> Hi, > > > >>> > > > >>> In ovirt-engine code we have Guid and NGuid > > > >>> objects. > > > >>> Guid is extends NGuid and also NGuid class has > > > >>> method > > > >>> getValue() > > > >>> which should return Guid. > > > >>> As for me these two classes are look like the > > > >>> same > > > >>> and > > > >>> I > > > >>> don't > > > >>> see > > > >>> to > > > >>> much differences between them. > > > >>> My proposal is to remove NGuid and move it > > > >>> functionality > > > >>> to > > > >>> Guid > > > >>> (Because of Guid is much more common) > > > >>> > > > >> i agree, but we need to take another step forward > > > >> and > > > >> allow > > > >> Guid > > > >> to > > > >> be null (as it should) > > > >> and not assume its EMPTY or have a value (i'm > > > >> pretty > > > >> sure > > > >> we > > > >> have > > > >> this assumption in many places) > > > > Hi, > > > > > > > > And for the new people out here... why not kill > > > > both > > > > and > > > > use > > > > plain > > > > standard java UUID[1]? > > > +1 for using java.util.UUID > > > > > > NGuid functionality that should be extracted during > > > the > > > refactor > > > is > > > - > > > 1. refactor DB and Java so empty or null return > > > values > > > are > > > null > > > and > > > not > > > EMPTY_GUID > > > 2. the special constructor of NGuid for UUID return > > > by > > > Microsoft > > > AD > > > should be extracted to a factory/utility > > > > I think we should kill compat, I don't see any > > > > value > > > > in > > > > fixing > > > > anything about it while leaving it intact. > > > > > > > > Regards, > > > > Alon Bar-Lev. > > > > > > > > [1] > > > > http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html > > Actually there is exists one reason not to use directly > > UUID > > at > > server side. > > The main operations on Guid today it is to convert > > object > > to > > Guid > > or > > Guid to string. > > Guid it is immutable object, number of Guids is limited > > and > > almost > > never changed, > > These sound like classical case for object that can be > > cached. > > Benefit - reduced number of string manipulations, > > reduced > > number > > of > > created instances, less work > > for garbage collection > > UUID has the same properties, it is immutable. So you > could > do > the > same with UUID, but I am not sure you could effectively > cache > these > objects and prove that you are saving either CPU, heap, > or > GC > time. These is a very common pattern: 1) implementation of valueOf() for most classes like Integer, Double, etc... has some kind of cache. 2) JVM has cache for strings that can be used and that cache can be tweaked by some JVM opts. 3) Most of our operations is perform query on DB, send request to host or parse response from host and Guid is very common object that is immutable. I am agree that these will not solve all our performance problems but can provide some benefit, especially when it is very easy to implement.
We could still achieve that using a UUIDCreator class and call it instead of Guid.fromString("")..
Whether this is cached or not is another question which can be solved later and checked to see if the cache improves performance or not. These is already implementation, if it will be Guid.fromString("") or UUIDCreator. The issue is if we want to use cache, it should be implemented together with deleting/replacing of Guid/NGuid , because of it much more easilly
I think the value of using standard java classes is higher than the tuning of the engine at this regard. Dropping the compat thing is important activity. Immutable object it is a common java design pattern After doing this conversion, use profiler to determine where major Already was done, and already tested a cache solution (Simple POC solution took to implement less
----- Original Message ----- than hour)
bottle necks are and fix these, I am not sure the above optimization will be first in list. Any optimization can not be first in the list, the best optimization is architecture change If we invest resources in optimization better to invest in these that we suffer most. Most of the issues are well known.
Please try to be less cryptic... Is this one of them?
Another issue, look at: http://www.2ality.com/2009/01/uuids-for-gwt.html GWT must have a wrapper for uuid, if removing Guid, we must override UUID in GWT. I'm +1 on leaving Guid for now. IMHO the bigger problem we have in the Guid area is the ambiguous use of Guid.Empty/null; for me Guid.Empty is BLANK_TEMPLTAE_UUID.
Regards, Alon
_______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
----- Original Message -----
From: "Alon Bar-Lev"<alonbl@redhat.com> To: "Michael Kublin"<mkublin@redhat.com> Cc: engine-devel@ovirt.org Sent: Tuesday, February 5, 2013 9:29:20 AM Subject: Re: [Engine-devel] Guid& NGuid
----- Original Message -----
From: "Michael Kublin"<mkublin@redhat.com> To: "Alon Bar-Lev"<alonbl@redhat.com> Cc: engine-devel@ovirt.org Sent: Tuesday, February 5, 2013 9:28:26 AM Subject: Re: [Engine-devel] Guid& NGuid
From: "Alon Bar-Lev"<alonbl@redhat.com> To: "Michael Kublin"<mkublin@redhat.com> Cc: engine-devel@ovirt.org Sent: Monday, February 4, 2013 4:17:39 PM Subject: Re: [Engine-devel] Guid& NGuid
From: "Michael Kublin"<mkublin@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 2:15:40 PM Subject: Re: [Engine-devel] Guid& NGuid
----- Original Message -----
From: "Mike Kolesnik"<mkolesni@redhat.com> To: "Michael Kublin"<mkublin@redhat.com> Cc: engine-devel@ovirt.org Sent: Monday, February 4, 2013 11:48:45 AM Subject: Re: [Engine-devel] Guid& NGuid
----- Original Message ----- > > ----- Original Message ----- >> From: "Laszlo Hornyak"<lhornyak@redhat.com> >> To: "Michael Kublin"<mkublin@redhat.com> >> Cc: engine-devel@ovirt.org >> Sent: Monday, February 4, 2013 9:56:28 AM >> Subject: Re: [Engine-devel] Guid& NGuid >> >> >> >> ----- Original Message ----- >>> From: "Michael Kublin"<mkublin@redhat.com> >>> To: engine-devel@ovirt.org >>> Sent: Monday, February 4, 2013 8:47:29 AM >>> Subject: Re: [Engine-devel] Guid& NGuid >>> >>> >>> >>> ----- Original Message ----- >>>> From: "Roy Golan"<rgolan@redhat.com> >>>> To: engine-devel@ovirt.org >>>> Sent: Monday, February 4, 2013 9:18:21 AM >>>> Subject: Re: [Engine-devel] Guid& NGuid >>>> >>>> On 02/03/2013 03:19 PM, Alon Bar-Lev wrote: >>>>> ----- Original Message ----- >>>>>> From: "Omer Frenkel"<ofrenkel@redhat.com> >>>>>> To: "Michael Kublin"<mkublin@redhat.com> >>>>>> Cc: "engine-devel"<engine-devel@ovirt.org> >>>>>> Sent: Sunday, February 3, 2013 3:12:19 PM >>>>>> Subject: Re: [Engine-devel] Guid& NGuid >>>>>> >>>>>> >>>>>> >>>>>> ----- Original Message ----- >>>>>>> From: "Michael Kublin"<mkublin@redhat.com> >>>>>>> To: "engine-devel"<engine-devel@ovirt.org> >>>>>>> Sent: Sunday, February 3, 2013 3:10:14 PM >>>>>>> Subject: [Engine-devel] Guid& NGuid >>>>>>> >>>>>>> Hi, >>>>>>> >>>>>>> In ovirt-engine code we have Guid and NGuid >>>>>>> objects. >>>>>>> Guid is extends NGuid and also NGuid class has >>>>>>> method >>>>>>> getValue() >>>>>>> which should return Guid. >>>>>>> As for me these two classes are look like the >>>>>>> same >>>>>>> and >>>>>>> I >>>>>>> don't >>>>>>> see >>>>>>> to >>>>>>> much differences between them. >>>>>>> My proposal is to remove NGuid and move it >>>>>>> functionality >>>>>>> to >>>>>>> Guid >>>>>>> (Because of Guid is much more common) >>>>>>> >>>>>> i agree, but we need to take another step forward >>>>>> and >>>>>> allow >>>>>> Guid >>>>>> to >>>>>> be null (as it should) >>>>>> and not assume its EMPTY or have a value (i'm >>>>>> pretty >>>>>> sure >>>>>> we >>>>>> have >>>>>> this assumption in many places) >>>>> Hi, >>>>> >>>>> And for the new people out here... why not kill >>>>> both >>>>> and >>>>> use >>>>> plain >>>>> standard java UUID[1]? >>>> +1 for using java.util.UUID >>>> >>>> NGuid functionality that should be extracted during >>>> the >>>> refactor >>>> is >>>> - >>>> 1. refactor DB and Java so empty or null return >>>> values >>>> are >>>> null >>>> and >>>> not >>>> EMPTY_GUID >>>> 2. the special constructor of NGuid for UUID return >>>> by >>>> Microsoft >>>> AD >>>> should be extracted to a factory/utility >>>>> I think we should kill compat, I don't see any >>>>> value >>>>> in >>>>> fixing >>>>> anything about it while leaving it intact. >>>>> >>>>> Regards, >>>>> Alon Bar-Lev. >>>>> >>>>> [1] >>>>> http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html >>> Actually there is exists one reason not to use directly >>> UUID >>> at >>> server side. >>> The main operations on Guid today it is to convert >>> object >>> to >>> Guid >>> or >>> Guid to string. >>> Guid it is immutable object, number of Guids is limited >>> and >>> almost >>> never changed, >>> These sound like classical case for object that can be >>> cached. >>> Benefit - reduced number of string manipulations, >>> reduced >>> number >>> of >>> created instances, less work >>> for garbage collection >> UUID has the same properties, it is immutable. So you >> could >> do >> the >> same with UUID, but I am not sure you could effectively >> cache >> these >> objects and prove that you are saving either CPU, heap, >> or >> GC >> time. > These is a very common pattern: > 1) implementation of valueOf() for most classes like > Integer, > Double, > etc... has some kind of cache. > 2) JVM has cache for strings that can be used and that > cache > can > be > tweaked by some JVM opts. > 3) Most of our operations is perform query on DB, send > request > to > host or parse response from host and Guid > is very common object that is immutable. > I am agree that these will not solve all our performance > problems > but > can provide some benefit, especially when it is very easy > to implement. We could still achieve that using a UUIDCreator class and call it instead of Guid.fromString("")..
Whether this is cached or not is another question which can be solved later and checked to see if the cache improves performance or not. These is already implementation, if it will be Guid.fromString("") or UUIDCreator. The issue is if we want to use cache, it should be implemented together with deleting/replacing of Guid/NGuid , because of it much more easilly I think the value of using standard java classes is higher than
----- Original Message ----- the tuning of the engine at this regard. Dropping the compat thing is important activity. Immutable object it is a common java design pattern After doing this conversion, use profiler to determine where major Already was done, and already tested a cache solution (Simple POC solution took to implement less
----- Original Message ----- than hour)
bottle necks are and fix these, I am not sure the above optimization will be first in list. Any optimization can not be first in the list, the best optimization is architecture change If we invest resources in optimization better to invest in these that we suffer most. Most of the issues are well known. Please try to be less cryptic... Is this one of them? Another issue, look at: http://www.2ality.com/2009/01/uuids-for-gwt.html GWT must have a wrapper for uuid, if removing Guid, we must override UUID in GWT. Not a serious issue, we have a uioverrides package anyway, we can make a wrapper in GWT I'm +1 on leaving Guid for now.
IMHO the bigger problem we have in the Guid area is the ambiguous use of Guid.Empty/null; for me Guid.Empty is BLANK_TEMPLTAE_UUID. That can indeed be an issue, there are thousands of references in the
On 02/10/2013 02:26 PM, Gilad Chaplik wrote: project to the wrapper classes, changing it at once might cause us NPEs from here to eternity
Regards, Alon
Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
_______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
Bare in mind there is some functionality about "byte reordering" of the GUID - if NGUID and GUID are to be removed, we should move this functionality to a utils class. ----- Original Message -----
From: "Roy Golan" <rgolan@redhat.com> To: engine-devel@ovirt.org Sent: Monday, February 4, 2013 9:18:21 AM Subject: Re: [Engine-devel] Guid & NGuid
On 02/03/2013 03:19 PM, Alon Bar-Lev wrote:
----- Original Message -----
From: "Omer Frenkel" <ofrenkel@redhat.com> To: "Michael Kublin" <mkublin@redhat.com> Cc: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:12:19 PM Subject: Re: [Engine-devel] Guid & NGuid
----- Original Message -----
From: "Michael Kublin" <mkublin@redhat.com> To: "engine-devel" <engine-devel@ovirt.org> Sent: Sunday, February 3, 2013 3:10:14 PM Subject: [Engine-devel] Guid & NGuid
Hi,
In ovirt-engine code we have Guid and NGuid objects. Guid is extends NGuid and also NGuid class has method getValue() which should return Guid. As for me these two classes are look like the same and I don't see to much differences between them. My proposal is to remove NGuid and move it functionality to Guid (Because of Guid is much more common)
i agree, but we need to take another step forward and allow Guid to be null (as it should) and not assume its EMPTY or have a value (i'm pretty sure we have this assumption in many places) Hi,
And for the new people out here... why not kill both and use plain standard java UUID[1]?
+1 for using java.util.UUID
NGuid functionality that should be extracted during the refactor is - 1. refactor DB and Java so empty or null return values are null and not EMPTY_GUID 2. the special constructor of NGuid for UUID return by Microsoft AD should be extracted to a factory/utility
I think we should kill compat, I don't see any value in fixing anything about it while leaving it intact.
Regards, Alon Bar-Lev.
[1] http://docs.oracle.com/javase/6/docs/api/java/util/UUID.html _______________________________________________ Engine-devel mailing list Engine-devel@ovirt.org http://lists.ovirt.org/mailman/listinfo/engine-devel
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participants (9)
-
Alon Bar-Lev -
Gilad Chaplik -
Laszlo Hornyak -
Michael Kublin -
Mike Kolesnik -
Omer Frenkel -
Roy Golan -
Tal Nisan -
Yair Zaslavsky