[ovirt-devel] Gluster Volume Snapshots - Feature review
Einav Cohen
ecohen at redhat.com
Thu Jan 1 17:06:03 UTC 2015
> ----- Original Message -----
> From: "Shubhendu Tripathi" <shtripat at redhat.com>
> Sent: Thursday, January 1, 2015 10:05:48 AM
>
> On 12/31/2014 11:42 PM, Einav Cohen wrote:
> > Thanks, Shubhendu. Additional comments:
> >
> >> ...
> >> Yes, attempt to create second snapshot schedule is actually an override
> >> option. Of course spot creation is allowed in addition to the scheduled.
> >> ...
> >> ...
> >> If the option Volumes -> Snapshots -> New selected, the dialog opens
> >> with pre-populated snapshot name prefix and Recurrence type selected as
> >> None by default. This effectively is one time snapshot creation.
> >> If this is first time and user wants to schedule the snapshot creation,
> >> he/she can change the recurrence type and provide details. Snapshot
> >> creation is scheduled in this case.
> >> Later, it user wants to edit the schedule, he/she needs to select option
> >> Volumes -> Snapshots -> Schedule (may be for this reason only I want to
> >> call it Edit Schedule). So effectively option Volumes -> Snapshots ->
> >> Schedule is meant for only re-scheduling the snapshot creation. If its
> >> not yet scheduled dialog opens with recurrence type selected as None.
> >> ...
> > From your latest responses, I conclude the following.
> >
> > via the "New" dialog, you can:
> >
> > (1) create a one-time snapshot
> > (2) create a new snapshot schedule
> > (3) override (and practically, edit) an existing snapshot schedule
> >
> > via the "Schedule" dialog, you can:
> >
> > (a) create a one-time snapshot (by selecting the 'None' recurrence)
> > (b) create a new snapshot schedule (by selecting something other than
> > 'None' in the recurrence field, given that no schedule exists yet)
> > (c) edit an existing snapshot schedule (which is what this dialog is
> > actually meant to do).
> >
> > I am not sure about (a), but it doesn't matter much for my point: "New"
> > and "Schedule" have the exact same functionality. To be more accurate:
> > "New" contains all of the needed functionality; "Schedule" is not really
> > needed. The only thing that "New" is potentially missing is showing the
> > values of the already-existing snapshot schedule, if one exists.
> >
> > I think that this may confuse to the user; I recommend to either
> > unite both of these actions/dialogs to a single action/dialog, or
> > separate completely some functionalists.
> >
> > So my recommendation is to do one of the following:
> >
> > (a) unite:
> > Have a single action ("Create / Schedule") which will display a
> > dialog very similar to the "New" dialog, with the option to see the
> > values of the already-existing snapshot schedule, if one exists.
> > In this case, I would actually recommend to go with something more
> > similar to option 2 in http://i.imgur.com/4j7hvRY.png, rather than
> > option 3 (so the separation between *creating new* *one-time*
> > snapshot and *editing an existing* *scheduled* snapshot is clearer).
> > see http://i.imgur.com/ZgCp9Tz.png for an updated suggestion.
> >
> > - or -
> >
> > (b) separate:
> > Have two completely separate actions: "Create Now" and "Schedule".
> >
> > - The "Create Now" dialog will look like the 'General' side-section
> > of the "New" dialog (i.e. without the "Schedule" side-section;
> > it will allow only one-time immediate snapshot creation.
> >
> > - The "Schedule" dialog will look like the "New" dialog (with both
> > 'General' and 'Schedule' side-sections) without the "None" recurrence,
> > and will allow only creating a new recurring snapshot schedule (if one
> > doesn't exist yet) or editing the existing schedule (in this case, the
> > dialog would be pre-populated with the values of the existing schedule).
> >
> > I am more in favor of (b) - it seems simpler and more user-friendly in
> > my view.
>
> Option (b) is something which we had started with, then at later stage
> it was discussed that scheduling as well should be in the flow of
> creation of snapshot so merged with New Snapshot option. After this as
> we need Edit option for snapshot schedule, so introduced Schedule option.
>
> But still, as you suggest I feel option (b) is no doubt a clearer and
> user friendly way.
>
> Alok, need a point of view from PMs on this.
Thanks, Shubhendu.
@Alok (and all):
the main pain-point in the current design that I am trying to address is
the fact that in the 'New' dialog, you have the option to create a one-
time snapshot, and within the same dialog, with a very small (too small
IMO) change, you have the option to edit (override) an already-existing
schedule, without even realizing necessarily that you are editing
something (since you are in a 'New' dialog) and without seeing the values
of the object that you are editing. From a UX perspective, this may be
confusing and misleading.
if it is imperative to combine the one-time creation functionality with
the scheduling functionality, you have option (a).
here is another option (c) that will allow you to create a one-time
snapshot and *create* a new schedule in the same dialog.
it is also probably the closest option to the original design in the
wiki, so I encourage you to consider it:
(c) Have two options, "New" and "Schedule", like today.
- "New" will be *only* for creating new objects, not editing/overriding
existing ones. It will look very similar to "New" in the current design,
including the "None" recurrence that I have suggested before.
* In case a schedule doesn't exist yet - "New" will have both the
'General' and 'Schedule' sections, like today, allowing creating a one-
time snapshot as well as creating a new snapshot schedule.
* In case a schedule already exists - "New" will have only the 'General'
side-section (the 'Schedule' side-section will not be displayed), allowing
only creation of new one-time snapshots.
- "Schedule":
* In case a schedule doesn't exist yet - two options:
i. disable this button (i.e. force the user to create a new schedule
via "New"); in this case, I agree with Shubhendu on renaming the button to
"Edit Schedule".
- or -
ii. have the dialog look exactly like "New" today, without the "None"
recurrence option; so only new schedule can be created, not one-time
snapshots. One-time snapshots should be created only via "New".
* In case a schedule already exists - the dialog will look like "New",
without the 'General' section (i.e. very similar to the mock-up of the
"Schedule" dialog in the ovirt wiki today), pre-populated with the current
values of the existing schedule.
Your thoughts/comments are welcome. Thank you.
>
>
> >
> > Your comments/thoughts are welcome.
> >
> > Thanks!
> >
> > ----
> > Regards,
> > Einav
> >
> > ----- Original Message -----
> >> From: "Shubhendu Tripathi" <shtripat at redhat.com>
> >> To: "Einav Cohen" <ecohen at redhat.com>
> >> Cc: devel at linode01.ovirt.org, "rhsc-dev" <rhsc-dev at redhat.com>
> >> Sent: Wednesday, December 31, 2014 12:56:44 AM
> >> Subject: Re: [ovirt-devel] Gluster Volume Snapshots - Feature review
> >>
> >> Hi Einav,
> >>
> >> Find the comments inline.
> >>
> >> Thanks and Regards,
> >> Shubhendu
> >>
> >> On 12/30/2014 11:13 PM, Einav Cohen wrote:
> >>> Thank you, Shubhendu! I have a few more comments:
> >>>
> >>>> Yes that's true for most of the cases. But having Options setting from
> >>>> sub-tab, not sure if that's correct. May be "New" is fine.
> >>> I think that if a user already got to the "Snapshots" sub-tab of a
> >>> specific Volume, it would seem strange that not all Snapshots-related
> >>> actions for that Volume are available from there - but I will leave it
> >>> to your discretion; I think that "New" is indeed the most important one
> >>> to have also in the sub-tab.
> >> We may have the New option available under sub tab as well. Setting
> >> configuration options would only be available in Volumes main tab.
> >>
> >>>> Once scheduled the only way to stop snapshot creation is to provide an
> >>>> end date.
> >>> let me try and understand what are the exact snapshot creation
> >>> capabilities.
> >>> consider the following use-cases (which may make absolutely no sense,
> >>> just giving these as examples in order to understand the capabilities):
> >>>
> >>> (1) let's say that I want to do two recurring snapshots schedules in
> >>> parallel for a single volume: one Monthly, and another one Weekly.
> >>> Can I do that?
> >> We can have only one schedule for a volume at a time.
> >>
> >>> I am assuming that I can't, i.e. there can only be one
> >>> recurring-snapshot-
> >>> creation schedule per volume (which you create via "New" and edit via
> >>> "Schedule") - is that correct? If so: are you blocking an attempt to
> >>> create a "New" recurring snapshot schedule when one already exists for
> >>> this Volume (e.g. disable the "New" button, fail a CanDoAction with a
> >>> message such as "Cannot create snapshot scheduling. A snapshot scheduling
> >>> already exists for this Volume", etc.) or allowing override of the
> >>> already-
> >>> existing schedule (with a proper warning)?
> >> Even if a volume snapshot creation is scheduled user can still opt for
> >> onetime spot snapshot creation and New would be available.
> >>
> >>> If my assumption is wrong, and I can have two (or more) recurring-
> >>> snapshot-creation schedules per volume: how do I *edit* these schedules?
> >>> what happens when I click on "Schedule"? which one of the two schedules
> >>> will I edit? The Weekly one? The Monthly one?
> >> As there is only one schedule for a volume at a time, so this is not
> >> valid scenario. Exiting single instance of schedule can be edited using
> >> the option Volumes -> Snapshots -> Schedule. May be if you suggest this
> >> option can be renamed to "Edit Schedule".
> >>
> >>> If I am comparing the terminology to the one of Calendar meeting schedule
> >>> (see http://i.imgur.com/xvf5w30.png): I don't have any "series" objects
> >>> that I can 'edit', I can see only "instances", and I can edit only one
> >>> "global" 'series' object via the "Schedule" button.
> >>> [again: if there can only be one recurring-snapshot-creation schedule per
> >>> volume, then the current design is OK, assuming the attempt to create a
> >>> second snapshot-schedule for a volume is properly blocked/overridden/...]
> >> Yes, attempt to create second snapshot schedule is actually an override
> >> option. Of course spot creation is allowed in addition to the scheduled.
> >>
> >>> (2) let's say that I want to do a weekly recurring snapshot scheduling
> >>> for
> >>> a certain volume. In addition to that weekly recurring snapshots, I want
> >>> to take a one-time snapshot of this volume right now. Can I do that?
> >> Yes, as discussed above stop one time creation in addition to the
> >> scheduled is allowed.
> >>
> >>> If so: then my suggestion [http://i.imgur.com/4j7hvRY.png, option 3] is
> >>> indeed valid; I am assuming that the user can create, per volume: one
> >>> recurring snapshot schedule + unlimited one-time snapshots.
> >> Yes. That's correct.
> >>
> >>> [If the user can create two (or more) recurring snapshot schedules - see
> >>> (1) above].
> >>> need to make sure that the user is able to create a "New" snapshot with
> >>> the "Weekly" recurrence schedule, and then another "New" snapshot(s) with
> >>> the "None" recurrence schedule, which will create the one-time
> >>> snapshot(s)
> >>> immediately, and that the schedule of the Weekly snapshot can be edited
> >>> via the "Schedule" option.
> >> So it goes like this. Say a Weekly snapshot is scheduled for certain
> >> volume and later user wants to create single on-spot snapshot. For this
> >> he/she need to select the option Volumes -> Snapshots -> New and not
> >> Volumes -> Snapshots -> Schedule. By default the option None is selected
> >> as Recurrence type and it creates a one time snapshot. Still the
> >> schedule stands valid in the system and if the user wants to edit the
> >> schedule he/she need to select the option Volumes -> Snapshots ->
> >> Schedule. Hope this clarifies.
> >>
> >>> If not (i.e. the user can create only one recurring snapshot schedule,
> >>> and that's it - no additional recurring snapshot schedules, no one-time
> >>> immediate snapshots, etc.), then my suggestion is invalid, and a 'None'
> >>> recurrence is not needed.
> >> As said above, one time snapshot creation is still allowed in addition
> >> to the scheduled. (Using Volumes -> Snapshots -> New option)
> >>
> >>> In this case, just need to make sure that the 'Schedule' side-section of
> >>> the dialog will be pre-populated with the most common/reasonable
> >>> recurrence
> >>> schedule, in case the user will not touch it.
> >>> BTW, if this is indeed the case, then there is probably no need for both
> >>> 'New' and 'Schedule' buttons - only 'Schedule' is sufficient.
> >>>
> >>>> Accept. The snapshot create dialog itself can be used here.
> >>> Just need to make sure to change its title accordingly (to 'Schedule
> >>> Snapshot' or something similar; right now it says "New Snapshot" in
> >>> the wiki).
> >>>
> >>> I assume that this dialog can be used for:
> >>>
> >>> (a) creating a New snapshot schedule (which should look very similar
> >>> to the 'New Snapshot' dialog, maybe with some pre-populated values,
> >>> maybe without the 'None' option in the Recurrence drop-down).
> >> If the option Volumes -> Snapshots -> New selected, the dialog opens
> >> with pre-populated snapshot name prefix and Recurrence type selected as
> >> None by default. This effectively is one time snapshot creation.
> >> If this is first time and user wants to schedule the snapshot creation,
> >> he/she can change the recurrence type and provide details. Snapshot
> >> creation is scheduled in this case.
> >> Later, it user wants to edit the schedule, he/she needs to select option
> >> Volumes -> Snapshots -> Schedule (may be for this reason only I want to
> >> call it Edit Schedule). So effectively option Volumes -> Snapshots ->
> >> Schedule is meant for only re-scheduling the snapshot creation. If its
> >> not yet scheduled dialog opens with recurrence type selected as None.
> >>
> >>> - and/or -
> >>>
> >>> (b) editing the already-existing schedule (in this case, fields that
> >>> cannot be edited should be disabled).
> >> As above.
> >>
> >>> I hope I was clear - please let me know if you have any questions or
> >>> comments.
> >>>
> >>> Thanks again!
> >>>
> >>> ----
> >>> Regards,
> >>> Einav
> >>>
> >>> ----- Original Message -----
> >>>> From: "Shubhendu Tripathi" <shtripat at redhat.com>
> >>>> To: "Einav Cohen" <ecohen at redhat.com>
> >>>> Cc: devel at linode01.ovirt.org, "rhsc-dev" <rhsc-dev at redhat.com>
> >>>> Sent: Tuesday, December 30, 2014 7:09:51 AM
> >>>> Subject: Re: [ovirt-devel] Gluster Volume Snapshots - Feature review
> >>>>
> >>>> Thanks Einav for the detailed review and your comments.
> >>>> Find below the comment inline.
> >>>>
> >>>> Will update the wiki accordingly and circulate.
> >>>>
> >>>> Team, please provide your thoughts (if conflicting) on this.
> >>>>
> >>>> Thanks and Regards,
> >>>> Shubhendu
> >>>>
> >>>> On 12/30/2014 05:33 AM, Einav Cohen wrote:
> >>>>> Hi Shubhendu,
> >>>>>
> >>>>> First of all - very detailed wiki pages (I focused mainly on the
> >>>>> User Experience part) - nicely done.
> >>>>>
> >>>>> I have a couple of comments / suggestions regarding the GUI:
> >>>>>
> >>>>> Snapshot action-group:
> >>>>>
> >>>>> - from the wiki page:
> >>>>> """
> >>>>> A new action-group "Snapshot" would be introduced under actions
> >>>>> for a volume.
> >>>>> """
> >>>>> I assume that you will implement it similarly to the "Power Management"
> >>>>> action-group (on Hosts main tab) or the "Profiling" action-group (on
> >>>>> the Volumes tab), i.e. with a drop-down-like styling
> >>>>> [http://i.imgur.com/eWRg6o8.png]?
> >>>> Yes. That's correct.
> >>>>
> >>>>> - If the Snapshot-related actions are expected to be core/critical in
> >>>>> the Volumes-related workflows, it makes sense to put them in the main-
> >>>>> tab, but please consider adding them to the Snapshots sub-tab as well,
> >>>>> in order to be consistent with other similar oVirt workflows.
> >>>> Yes that's true for most of the cases. But having Options setting from
> >>>> sub-tab, not sure if that's correct. May be "New" is fine.
> >>>>
> >>>>> New Snapshot dialog -> Schedule section:
> >>>>>
> >>>>> - I suggest to implement the time-interval selection with a drop-down,
> >>>>> rather than a radio-button group; it is more consistent with e.g.
> >>>>> event-repeat scheduling in a calendar [http://i.imgur.com/y9Gn3wq.png],
> >>>>> it will save real-estate within the dialog and it will be more easily
> >>>>> readable for the user.
> >>>> That's a good suggestion. Will do this.
> >>>>
> >>>>> - to my understanding, the New Snapshot functionality doesn't have to
> >>>>> be recurrent; however, there isn't any way to "disable" the recurring
> >>>>> aspect. Here are some suggestions to how this should be added:
> >>>>> http://i.imgur.com/4j7hvRY.png
> >>>> Once scheduled the only way to stop snapshot creation is to provide an
> >>>> end date.
> >>>>
> >>>>> Option 3 is my personal favorite - it is the simplest, and is
> >>>>> consistent
> >>>>> with Calendear-scheduling UI. Option 1 is my least favorite, however it
> >>>>> is consistent with e.g. the "Enable Power Management" UI within the
> >>>>> "New
> >>>>> Host" dialog.
> >>>> Option-3 looks good to me as well. Should be doable I feel.
> >>>>
> >>>>> Snapshots -> Options:
> >>>>>
> >>>>> - I think that there are a couple of problematic issues with this
> >>>>> dialog:
> >>>>>
> >>>>> * the different functionality of this dialog when a Volume is
> >>>>> selected
> >>>>> vs. when no Volume is selected may be unclear to the user.
> >>>> Agree
> >>>>
> >>>>>
> >>>>> * the fact that we can update Cluster-related parameters (which
> >>>>> potentially affects *all* volumes in that Cluster) within a specific
> >>>>> Volume-context dialog is a bit risky - and we don't have anything
> >>>>> similar
> >>>>> to that anywhere in the application today IIRC.
> >>>>>
> >>>>> my recommendations:
> >>>>>
> >>>>> * have separate "Options - Cluster" and "Options - Volume"
> >>>>> actions;
> >>>>> "Options - Cluster" should always be enabled.
> >>>>> "Options - Volume" should be enabled only when a Volume is selected.
> >>>> Accept
> >>>>
> >>>>> * Seehttp://i.imgur.com/pfRpjrH.png for my suggestion for
> >>>>> "Cluster
> >>>>> Options" vs. "Volume Options". Note that from the "Volume Options"
> >>>>> dialog, you may allow editing the Cluster Options by clicking on the
> >>>>> link-button, which will either (a) open the "Cluster Options" dialog
> >>>>> on top or (b) allow editing the Cluster Values inline within the
> >>>>> already-open dialog - this should be accompanied with a clear note to
> >>>>> the user that he is editing Cluster-related parameters from the current
> >>>>> (Volume) context, which may affect *all* Volumes in that Cluster.
> >>>>> Also note that in my suggestion, the user can conveniently see both the
> >>>>> Volume values and the Cluster Values side-by-side at once, for
> >>>>> reference.
> >>>> Accept
> >>>>
> >>>>> Snapshots -> Schedule:
> >>>>>
> >>>>> - to my understanding, this should be very similar (or identical) to
> >>>>> the
> >>>>> New Snapshot functionality? if so, we may want to simply open the "New
> >>>>> Snapshot" dialog focused on the "Schedule" side-section (rather than
> >>>>> the
> >>>>> 'General' side-section, maybe already pre-populated with some values in
> >>>>> the 'General' side-section (which will still be editable by the user)
> >>>>> and
> >>>>> something already pre-selected in the (focused) "Schedule" section.
> >>>>>
> >>>>> please let me know whether you think these can/should be incorporated
> >>>>> into the design, and/or if you have any comments or questions.
> >>>> Accept. The snapshot create dialog itself can be used here.
> >>>>
> >>>>> thanks.
> >>>>>
> >>>>> ----
> >>>>> Regards,
> >>>>> Einav
> >>>>>
> >>>>> ----- Original Message -----
> >>>>>> From: "Shubhendu Tripathi"<shtripat at redhat.com>
> >>>>>> To:devel at linode01.ovirt.org,jhernand at redhat.com, "Michael
> >>>>>> Pasternak"<mpastern at redhat.com>
> >>>>>> Sent: Monday, November 10, 2014 1:52:40 AM
> >>>>>> Subject: [ovirt-devel] Gluster Volume Snapshots - Feature review
> >>>>>>
> >>>>>> Hi All,
> >>>>>>
> >>>>>> Please help us to review the design of Gluster Volume Snapshots in
> >>>>>> oVirt,
> >>>>>>
> >>>>>> Here are two design on wiki page
> >>>>>>
> >>>>>> General Feature Design
> >>>>>> http://www.ovirt.org/Features/GlusterVolumeSnapshots
> >>>>>>
> >>>>>> Detailed Design
> >>>>>> http://www.ovirt.org/Features/Design/GlusterVolumeSnapshots
> >>>>>>
> >>>>>> We target it in ovirt 3.6 release.
> >>>>>>
> >>>>>> Marked Juan/Michael specifically for REST review.
> >>>>>>
> >>>>>> Best Regards,
> >>>>>> Shubhendu Tripathi
> >>>>>> _______________________________________________
> >>>>>> Devel mailing list
> >>>>>> Devel at ovirt.org
> >>>>>> http://lists.ovirt.org/mailman/listinfo/devel
> >>>>>>
> >>
>
>
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