[Engine-devel] [UX] how to design a bar/line chart?

Einav Cohen ecohen at redhat.com
Wed Nov 13 13:59:48 UTC 2013 

> ----- Original Message -----
> From: "Tomas Jelinek" <tjelinek at redhat.com>
> Sent: Wednesday, November 13, 2013 8:42:40 AM
> 
> 
> 
> ----- Original Message -----
> > From: "Tomas Jelinek" <tjelinek at redhat.com>
> > To: awels at redhat.com
> > Cc: "Eldan Hildesheim" <ehildesh at redhat.com>, engine-devel at ovirt.org,
> > "info" <info at eldanet.com>
> > Sent: Wednesday, November 13, 2013 8:21:56 AM
> > Subject: Re: [Engine-devel] [UX] how to design a bar/line chart?
> > 
> > 
> > 
> > ----- Original Message -----
> > > From: "Alexander Wels" <awels at redhat.com>
> > > To: "Tomas Jelinek" <tjelinek at redhat.com>
> > > Cc: engine-devel at ovirt.org, "Michal Skrivanek"
> > > <michal.skrivanek at redhat.com>, "Eldan Hildesheim"
> > > <ehildesh at redhat.com>, "info" <info at eldanet.com>
> > > Sent: Tuesday, November 12, 2013 4:52:12 PM
> > > Subject: Re: [Engine-devel] [UX] how to design a bar/line chart?
> > > 
> > > On Tuesday, November 12, 2013 10:21:15 AM Tomas Jelinek wrote:
> > > > ----- Original Message -----
> > > > 
> > > > > From: "Alexander Wels" <awels at redhat.com>
> > > > > To: "Tomas Jelinek" <tjelinek at redhat.com>
> > > > > Cc: engine-devel at ovirt.org, "Michal Skrivanek"
> > > > > <michal.skrivanek at redhat.com>, "Eldan Hildesheim"
> > > > > <ehildesh at redhat.com>,
> > > > > "info" <info at eldanet.com>
> > > > > Sent: Tuesday, November 12, 2013 4:03:14 PM
> > > > > Subject: Re: [Engine-devel] [UX] how to design a bar/line chart?
> > > > > 
> > > > > On Tuesday, November 12, 2013 09:50:07 AM Tomas Jelinek wrote:
> > > > > > ----- Original Message -----
> > > > > > 
> > > > > > > From: "Alexander Wels" <awels at redhat.com>
> > > > > > > To: engine-devel at ovirt.org
> > > > > > > Cc: "Tomas Jelinek" <tjelinek at redhat.com>, "Michal Skrivanek"
> > > > > > > <michal.skrivanek at redhat.com>, "Eldan Hildesheim"
> > > > > > > <ehildesh at redhat.com>,
> > > > > > > "info" <info at eldanet.com>
> > > > > > > Sent: Tuesday, November 12, 2013 3:33:56 PM
> > > > > > > Subject: Re: [Engine-devel] [UX] how to design a bar/line chart?
> > > > > > > 
> > > > > > > On Tuesday, November 12, 2013 09:25:34 AM Tomas Jelinek wrote:
> > > > > > > > Hey all,
> > > > > > > > 
> > > > > > > > let me conclude what has been written in this thread to one
> > > > > > > > proposal:
> > > > > > > > 
> > > > > > > > == From the UX perspective the behavior ==
> > > > > > > > - each time the FE will receive new data and this data are
> > > > > > > > different
> > > > > > > > from
> > > > > > > > the old ones, visualize it in the chart It means if you will
> > > > > > > > keep
> > > > > > > > pressing
> > > > > > > > the refresh button but the data will not change, no new data
> > > > > > > > will
> > > > > > > > be
> > > > > > > > visualized (an exception will be the 0 usage) - the amount of
> > > > > > > > data
> > > > > > > > visualized will depend on the size of the widget (since the
> > > > > > > > tables
> > > > > > > > are
> > > > > > > > resizable). It means that if you make the widget bigger you
> > > > > > > > will
> > > > > > > > not
> > > > > > > > see
> > > > > > > > the same chart bigger but more data. - If you make the widget
> > > > > > > > bigger,
> > > > > > > > only
> > > > > > > > then the amount of data will start to increase: e.g.
> > > > > > > > 
> > > > > > > > before resize:
> > > > > > > > | /-------\ |
> > > > > > > > |
> > > > > > > > |/         \|
> > > > > > > > 
> > > > > > > > after resize:
> > > > > > > > | /-------\          |
> > > > > > > > |
> > > > > > > > |/         \         |
> > > > > > > > 
> > > > > > > > and only now the new data will start to appear
> > > > > > > > 
> > > > > > > > == From FE technical point of view ==
> > > > > > > > - since I have not found any GWT library which would be
> > > > > > > > acceptable
> > > > > > > > (e.g.
> > > > > > > > actively developed and without the need to connect to google
> > > > > > > > servers)
> > > > > > > > and
> > > > > > > > given that the required chart is quite simple I guess it would
> > > > > > > > be
> > > > > > > > ok
> > > > > > > > to
> > > > > > > > write it by myself. - according to Einav's mail it is ok to use
> > > > > > > > HTML5
> > > > > > > > canvas so I would go with writing a new widget using HTML5
> > > > > > > > canvas
> > > > > > > 
> > > > > > > Just to throw out something to think about, we could also in
> > > > > > > theory
> > > > > > > generate an image on the server side and simply display that
> > > > > > > image
> > > > > > > inside
> > > > > > > the grid (so no need for HTML5 canvas or other things like that).
> > > > > > > The
> > > > > > > idea being basically that when the grid refreshes it makes a
> > > > > > > request
> > > > > > > for
> > > > > > > a new image on the back- end with the appropriate timeframe and
> > > > > > > the
> > > > > > > back-end generates the image which is easy to embed inside the
> > > > > > > grid.
> > > > > > > 
> > > > > > > pros:
> > > > > > > * Easy to embed inside grid (just an image tag).
> > > > > > > * Works on all browsers, even ones without HTML5 canvas support.
> > > > > > > cons:
> > > > > > > * More load on the back-end.
> > > > > > > * Extra round trips to back-end on refresh.
> > > > > > > * Not 'hot' like HTML5 canvas.
> > > > > > > * No interactivity if that is something we are interested in.
> > > > > > 
> > > > > > some more cons:
> > > > > > * need to remember the statistics on server in the memory. For
> > > > > > thousands
> > > > > > of
> > > > > > VMs it is not something we would like to do * lots of overhead to
> > > > > > retrieve
> > > > > > all the images on each refresh. If you have 100 VMs on a page and
> > > > > > refresh
> > > > > > each 5 seconds, it is 100 images transmitted from engine to
> > > > > > frontend
> > > > > > each 5
> > > > > > seconds per one client (and we can have more of them of course) *
> > > > > > FE
> > > > > > logic
> > > > > > on Server is in general not awesome
> > > > > 
> > > > > I would expect the statistics to be stored in the database somewhere,
> > > > > that
> > > > > way
> > > > > we can pull them for reports and things of that nature (like charts).
> > > > > Obviously we wouldn't do 100 round trips for the image, we would
> > > > > generate
> > > > > a
> > > > > single image sprite that would contain all the images in a single
> > > > > request
> > > > > and display the appropriate part of the image in the grid.
> > > > > 
> > > > > You are right in general front-end logic is not done on the back-end.
> > > > > However we must consider if we are really doing front end logic here,
> > > > > or
> > > > > if we are just displaying some reporting information as part of the
> > > > > grid.
> > > > > 
> > > > > If we are not storing the statistics anywhere, then this is a
> > > > > terrible
> > > > > plan, and we should do the logic on the client, but if we are, it is
> > > > > something to consider.
> > > > 
> > > > We store only the actual value. The statistics are stored only by DWH
> > > > but that is a different application. Engine itself does not have it so
> > > > we
> > > > would have to implement it.
> > > > 
> > > 
> > > Which as you mentioned is not a desirable thing to do for thousands of
> > > VMs,
> > > but does bring up the question, if we only aggregate the statistics on
> > > the
> > > client, do we care if that information is lost when the user logs
> > > out/switches
> > > tab/etc. Since essentially we stop requesting that information from the
> > > back-
> > > end if the current active tab is not the VM main tab.
> > 
> > I would say it is not a problem. The VM tab is not for detailed statistics
> > or
> > history data.
> > For this kind of data we have the reports portal.
> > 
> > On the other hand it may be painful to go to the VM tab and see no
> > statistics
> > and get them updated
> > each 15 seconds. So after couple of minutes you will maybe see something
> > useful. Just don't click on any
> > other tab, otherwise you will loose that all :)
> > 
> > @Michal,Einav: Is this acceptable?
> 
> OK, after some more discussions with Michal about the idea of having some
> history data in our DB it starts to look like a really good idea.
> 
> What about this solution:
> Let's store the last N results of VDSM poll in the vm_dynamic table instead
> of the last one only
> (where the N would be configured in vdc_options and by default something like
> 10).
> Let's send this to client so the client will be able to draw a nice chart out
> of all the values which are available.
> 
> It would have this advantages:
> Technical:
> - no lost data caused by slower polling of engine by FE than is the polling
> of the VDSM by engine
> - consequently no need to do any interpolations because the data are already
> averaged by VDSM and I have no "holes" in between
> - also no problems to "ignore" updates caused by faster refresh of engine by
> FE than the poll of VDSM by engine
> 
> UX:
> - after the first load of the VM tab the data shown in this tab would already
> be useful - no need to wait couple of refresh cycles until I get enough poll
> results
> - I can freely jump from tab to tab without the fear to loose all precious
> data I have in this tab collected
> 
> Disadvantage is that we would have to store a bit more data on the server
> (but not much more since we would remember only couple of polls) and a bit
> more data transferred to client.
> 
> What do you guys think?

+1 on this suggestion, I like it a lot.

I am concerned about one thing that you mentioned yesterday (which I don't think 
is relevant anymore with this new suggestion, but just in case):

"""
== From the UX perspective the behavior ==
- each time the FE will receive new data and this data are different from the old ones, visualize it in the chart
  It means if you will keep pressing the refresh button but the data will not change, no new data will be visualized (an exception will be the 0 usage)
"""

IIUC, it means that if the CPU is constantly 5% and it spikes to 100% once an hour, 
we will see a graph of 5%-100%-5%-100% (over a *long* period of time though), which 
may seem like the VM is spiking half of its time, which is misleading.

But with the new approach of persisting the "historic" info in the DB, this will 
not be the case anymore, correct?


> 
> > 
> > > 
> > > > > > > > == From L&F point of view ==
> > > > > > > > - would look pretty much like the one proposed by Malini:
> > > > > > > > http://style.org/chartapi/sparklines/
> > > > > > > > 
> > > > > > > > == From data point of view ==
> > > > > > > > - do not do any averages on VDSM side (since it already does
> > > > > > > > them
> > > > > > > > for
> > > > > > > > CPU
> > > > > > > > and network and the memory is stable enough) - do not do any
> > > > > > > > averages
> > > > > > > > on
> > > > > > > > engine side (since would have to be done for each FE separately
> > > > > > > > and
> > > > > > > > stored
> > > > > > > > in session which is a bit overcomplicated. If the user wants to
> > > > > > > > see
> > > > > > > > more
> > > > > > > > accurate data, he/she can change the refresh rate) - do not do
> > > > > > > > any
> > > > > > > > interpolation since the data are already averaged and we will
> > > > > > > > show
> > > > > > > > only
> > > > > > > > new
> > > > > > > > ones
> > > > > > > > 
> > > > > > > > @Malini,Einav,Eldan,Michal what do you think?
> > > > > > > > 
> > > > > > > > Tomas
> > > > > > > > 
> > > > > > > > ----- Original Message -----
> > > > > > > > 
> > > > > > > > > From: "Michal Skrivanek" <michal.skrivanek at redhat.com>
> > > > > > > > > To: "Tomas Jelinek" <tjelinek at redhat.com>, "Dan Kenigsberg"
> > > > > > > > > <danken at redhat.com> Cc: "Malini Rao" <mrao at redhat.com>,
> > > > > > > > > "Eldan
> > > > > > > > > Hildesheim" <ehildesh at redhat.com>, engine-devel at ovirt.org,
> > > > > > > > > "info"
> > > > > > > > > <info at eldanet.com>
> > > > > > > > > Sent: Tuesday, November 12, 2013 11:49:12 AM
> > > > > > > > > Subject: Re: [Engine-devel] [UX] how to design a bar/line
> > > > > > > > > chart?
> > > > > > > > > 
> > > > > > > > > On Nov 12, 2013, at 11:18 , Tomas Jelinek
> > > > > > > > > <tjelinek at redhat.com>
> > > > > > > > > 
> > > > > > > > > wrote:
> > > > > > > > > > So we have looked into the resource usage sampling with
> > > > > > > > > > mbetak
> > > > > > > > > > and
> > > > > > > > > > also
> > > > > > > > > > with Michal and it seems that
> > > > > > > > > > 
> > > > > > > > > > for the CPU usage:
> > > > > > > > > > - VDSM polls libvirt to get the runtime statistics of the
> > > > > > > > > > VM
> > > > > > > > > > regularly.
> > > > > > > > > > The
> > > > > > > > > > pooling interval is configured in
> > > > > > > > > > 
> > > > > > > > > >  vdsm.conf as vm_sample_cpu_interval and by default it is
> > > > > > > > > >  15
> > > > > > > > > >  seconds
> > > > > > > > > > 
> > > > > > > > > > - libvirt returns something we than use to calculate the
> > > > > > > > > > average
> > > > > > > > > > CPU
> > > > > > > > > > usage
> > > > > > > > > > since the last poll
> > > > > > > > > > - engine polls VDSM once in 15 seconds to get the current
> > > > > > > > > > statistics
> > > > > > > > > > (the
> > > > > > > > > > same 15 seconds is just a coincidence and we can not count
> > > > > > > > > > on
> > > > > > > > > > this)
> > > > > > > > > > - than the frontend polls the engine each 5-60 seconds
> > > > > > > > > > (depends
> > > > > > > > > > on
> > > > > > > > > > the
> > > > > > > > > > refresh rate) and gets the current value from the engine
> > > > > > > > > > - the user can press the refresh button anytime to poll the
> > > > > > > > > > engine
> > > > > > > > > > again
> > > > > > > > > > 
> > > > > > > > > > For network usage:
> > > > > > > > > > - it should be pretty much the same as the CPU just the
> > > > > > > > > > VDSM
> > > > > > > > > > poll
> > > > > > > > > > interval
> > > > > > > > > > is configured as vm_sample_net_interval and by default it
> > > > > > > > > > is
> > > > > > > > > > 5
> > > > > > > > > > seconds
> > > > > > > > > 
> > > > > > > > > Dan, since we poll only every 15s and cpu info is 15s
> > > > > > > > > wouldn't
> > > > > > > > > it
> > > > > > > > > make
> > > > > > > > > sense to change the default for network monitoring to 15s as
> > > > > > > > > well?
> > > > > > > > > it's 2
> > > > > > > > > libvirt rounds trip for nothing really. Or does it serve some
> > > > > > > > > other
> > > > > > > > > purpose?>
> > > > > > > > > 
> > > > > > > > > > For memory usage:
> > > > > > > > > > - guest agent sends a message to VDSM with the memory usage
> > > > > > > > > > regularly.
> > > > > > > > > > The
> > > > > > > > > > interval is set in ovirt-guest-agent.conf as
> > > > > > > > > > heart_beat_rate
> > > > > > > > > > 
> > > > > > > > > >  and by default it is 5 seconds
> > > > > > > > > > 
> > > > > > > > > > - the actual value sent by ovirt-guest-agent is the actual
> > > > > > > > > > value
> > > > > > > > > > at
> > > > > > > > > > the
> > > > > > > > > > time when the value is sent (e.g. for Linux taken from "cat
> > > > > > > > > > /proc/meminfo")
> > > > > > > > > > - vdsm is doing no statistics on top of it, just remembers
> > > > > > > > > > the
> > > > > > > > > > last
> > > > > > > > > > value
> > > > > > > > > > taken from ovirt-guest-agent
> > > > > > > > > 
> > > > > > > > > which is fine, it doesn't change so often and there are
> > > > > > > > > typically
> > > > > > > > > no
> > > > > > > > > spikes
> > > > > > > > > 
> > > > > > > > > > - the rest of the poling is the same
> > > > > > > > > > 
> > > > > > > > > > So, visualizing this in some usable form will be quite
> > > > > > > > > > challenging
> > > > > > > > > > ;)
> > > > > > > > > > I see the following problems:
> > > > > > > > > > - if the VDSM gets the data faster than the engine polls it
> > > > > > > > > > (and
> > > > > > > > > > most
> > > > > > > > > > often
> > > > > > > > > > it does) than the info in between will be lost.
> > > > > > > > > > 
> > > > > > > > > >  The question is how big this problem is and if it is worth
> > > > > > > > > >  solving
> > > > > > > > > >  (I
> > > > > > > > > >  would say not for CPU which are averages but maybe yes for
> > > > > > > > > >  memory).
> > > > > > > > > >  Other question if there is a way how to solve it since the
> > > > > > > > > >  VDSM
> > > > > > > > > >  can
> > > > > > > > > >  be
> > > > > > > > > >  polled by anyone and it does not really care if someone
> > > > > > > > > >  polls
> > > > > > > > > >  it...
> > > > > > > > > >  (Michal?)
> > > > > > > > > 
> > > > > > > > > I'd say not solve it and try to keep it in sync on vdsm side
> > > > > > > > > with
> > > > > > > > > engine
> > > > > > > > > poll, to save unnecessary libvirt calls
> > > > > > > > > 
> > > > > > > > > > - we can lost some data between frontend<->engine if the
> > > > > > > > > > polling
> > > > > > > > > > interval
> > > > > > > > > > of the FE is slower than the polling interval of the
> > > > > > > > > > engine.
> > > > > > > > > > This
> > > > > > > > > > is
> > > > > > > > > > something
> > > > > > > > > > 
> > > > > > > > > >  not really worth solving because the user can set this
> > > > > > > > > >  according
> > > > > > > > > >  to
> > > > > > > > > >  the
> > > > > > > > > >  level of detail he/she wants
> > > > > > > > > 
> > > > > > > > > well, you should average the values in engine in case the FE
> > > > > > > > > refresh
> > > > > > > > > is
> > > > > > > > > 
> > > > > > > > > >15s. Or add (refresh/15) of them
> > > > > > > > 
> > > > > > > > It is not that simple since you can have more frontends and not
> > > > > > > > sure
> > > > > > > > if
> > > > > > > > it
> > > > > > > > would be a good idea to put this into the session...
> > > > > > > > 
> > > > > > > > > > - since we will get new info once in ~15 seconds, and the
> > > > > > > > > > polling
> > > > > > > > > > of
> > > > > > > > > > the
> > > > > > > > > > FE
> > > > > > > > > > is by default 5 seconds, do we want to do some
> > > > > > > > > > interpolation?
> > > > > > > > > > Or
> > > > > > > > > > just
> > > > > > > > > > show
> > > > > > > > > > the
> > > > > > > > > > 
> > > > > > > > > >  same value 3 times? Or be smart and show only changed
> > > > > > > > > >  values?
> > > > > > > > > >  (this
> > > > > > > > > >  is
> > > > > > > > > >  tricky since there is a chance that it did not change -
> > > > > > > > > >  e.g.
> > > > > > > > > >  constant
> > > > > > > > > >  0
> > > > > > > > > >  mem usage if you have no guest agent)
> > > > > > > > > > 
> > > > > > > > > > - What if the user starts clicking to the refresh button?
> > > > > > > > > > Do
> > > > > > > > > > we
> > > > > > > > > > want
> > > > > > > > > > to
> > > > > > > > > > keep appending the same value if the engine still has only
> > > > > > > > > > the
> > > > > > > > > > old
> > > > > > > > > > ones?
> > > > > > > > > 
> > > > > > > > > just add a new line/point every 15s should be ok
> > > > > > > > > 
> > > > > > > > > Thanks,
> > > > > > > > > michal
> > > > > > > > > 
> > > > > > > > > > Tomas
> > > > > > > > > > 
> > > > > > > > > > ----- Original Message -----
> > > > > > > > > > 
> > > > > > > > > >> From: "Tomas Jelinek" <tjelinek at redhat.com>
> > > > > > > > > >> To: "Malini Rao" <mrao at redhat.com>
> > > > > > > > > >> Cc: "Eldan Hildesheim" <ehildesh at redhat.com>,
> > > > > > > > > >> engine-devel at ovirt.org,
> > > > > > > > > >> "info" <info at eldanet.com>
> > > > > > > > > >> Sent: Monday, November 11, 2013 4:23:09 PM
> > > > > > > > > >> Subject: Re: [Engine-devel] [UX] how to design a bar/line
> > > > > > > > > >> chart?
> > > > > > > > > >> 
> > > > > > > > > >> 
> > > > > > > > > >> 
> > > > > > > > > >> ----- Original Message -----
> > > > > > > > > >> 
> > > > > > > > > >>> From: "Malini Rao" <mrao at redhat.com>
> > > > > > > > > >>> To: "Eldan Hildesheim" <ehildesh at redhat.com>
> > > > > > > > > >>> Cc: "Tomas Jelinek" <tjelinek at redhat.com>, "info"
> > > > > > > > > >>> <info at eldanet.com>,
> > > > > > > > > >>> engine-devel at ovirt.org
> > > > > > > > > >>> Sent: Monday, November 11, 2013 4:15:50 PM
> > > > > > > > > >>> Subject: Re: [Engine-devel] [UX] how to design a bar/line
> > > > > > > > > >>> chart?
> > > > > > > > > >>> 
> > > > > > > > > >>> Is this going to fit in a row of a table? Or are we
> > > > > > > > > >>> talking
> > > > > > > > > >>> of
> > > > > > > > > >>> a
> > > > > > > > > >>> more
> > > > > > > > > >>> detailed view?
> > > > > > > > > >> 
> > > > > > > > > >> it should fit into one cell of the table
> > > > > > > > > >> 
> > > > > > > > > >>> ----- Original Message -----
> > > > > > > > > >>> From: "Eldan Hildesheim" <ehildesh at redhat.com>
> > > > > > > > > >>> To: "Tomas Jelinek" <tjelinek at redhat.com>
> > > > > > > > > >>> Cc: "info" <info at eldanet.com>, engine-devel at ovirt.org
> > > > > > > > > >>> Sent: Monday, November 11, 2013 8:01:07 AM
> > > > > > > > > >>> Subject: Re: [Engine-devel] [UX] how to design a bar/line
> > > > > > > > > >>> chart?
> > > > > > > > > >>> 
> > > > > > > > > >>> Throw this gif into a browser. This is more or less what
> > > > > > > > > >>> I
> > > > > > > > > >>> thought.
> > > > > > > > > >>> Eldan
> > > > > > > > > >>> 
> > > > > > > > > >>> ----- Original Message -----
> > > > > > > > > >>> From: "Tomas Jelinek" <tjelinek at redhat.com>
> > > > > > > > > >>> To: "Eldan Hildesheim" <ehildesh at redhat.com>
> > > > > > > > > >>> Cc: "Einav Cohen" <ecohen at redhat.com>, "info"
> > > > > > > > > >>> <info at eldanet.com>,
> > > > > > > > > >>> engine-devel at ovirt.org
> > > > > > > > > >>> Sent: Monday, November 11, 2013 12:03:15 PM
> > > > > > > > > >>> Subject: Re: [Engine-devel] [UX] how to design a bar/line
> > > > > > > > > >>> chart?
> > > > > > > > > >>> 
> > > > > > > > > >>> 
> > > > > > > > > >>> 
> > > > > > > > > >>> ----- Original Message -----
> > > > > > > > > >>> 
> > > > > > > > > >>>> From: "Eldan Hildesheim" <ehildesh at redhat.com>
> > > > > > > > > >>>> To: "Einav Cohen" <ecohen at redhat.com>
> > > > > > > > > >>>> Cc: "info" <info at eldanet.com>, engine-devel at ovirt.org
> > > > > > > > > >>>> Sent: Sunday, November 10, 2013 3:56:57 PM
> > > > > > > > > >>>> Subject: Re: [Engine-devel] [UX] how to design a
> > > > > > > > > >>>> bar/line
> > > > > > > > > >>>> chart?
> > > > > > > > > >>>> 
> > > > > > > > > >>>> Hello all,
> > > > > > > > > >>>> We use to have a good solution in the period pre-WPF.
> > > > > > > > > >>>> A line chart (used to be in flash) that works like a
> > > > > > > > > >>>> plotter:
> > > > > > > > > >>>> The Line Bar (not bar) had a small animation that
> > > > > > > > > >>>> shifted
> > > > > > > > > >>>> all
> > > > > > > > > >>>> the
> > > > > > > > > >>>> bar
> > > > > > > > > >>>> to
> > > > > > > > > >>>> the
> > > > > > > > > >>>> left.
> > > > > > > > > >>>> When a new data arrived it just added a new line (to the
> > > > > > > > > >>>> right)
> > > > > > > > > >>>> and
> > > > > > > > > >>>> as I
> > > > > > > > > >>>> said
> > > > > > > > > >>>> before, in parallel it always shifted slowly to the
> > > > > > > > > >>>> left.
> > > > > > > > > >>> 
> > > > > > > > > >>> Any chance you still have some screenshot or mockup so I
> > > > > > > > > >>> can
> > > > > > > > > >>> imagine
> > > > > > > > > >>> it
> > > > > > > > > >>> better?
> > > > > > > > > >>> 
> > > > > > > > > >>>> The animation gives the impression that data is
> > > > > > > > > >>>> streaming
> > > > > > > > > >>>> and
> > > > > > > > > >>>> when a
> > > > > > > > > >>>> real
> > > > > > > > > >>>> new
> > > > > > > > > >>>> data arrives the user gets it very fast.
> > > > > > > > > >>>> We have to sync between the animation and the rate of
> > > > > > > > > >>>> the
> > > > > > > > > >>>> arrival
> > > > > > > > > >>>> of
> > > > > > > > > >>>> the
> > > > > > > > > >>>> data
> > > > > > > > > >>>> but this is easy.
> > > > > > > > > >>>> If we can't find a good framework it can be created from
> > > > > > > > > >>>> scratch
> > > > > > > > > >>>> with
> > > > > > > > > >>>> JS,
> > > > > > > > > >>>> svg
> > > > > > > > > >>>> or canvas.
> > > > > > > > > >>> 
> > > > > > > > > >>> We need to be careful about what we will use. oVirt is
> > > > > > > > > >>> supposed
> > > > > > > > > >>> to
> > > > > > > > > >>> work
> > > > > > > > > >>> on
> > > > > > > > > >>> FF
> > > > > > > > > >>> 17 [1]
> > > > > > > > > >>> but the HTML5 canvas works only since FF23 [2].
> > > > > > > > > >>> 
> > > > > > > > > >>> @Einav:
> > > > > > > > > >>> Is there a chance that we could start support only FF23+
> > > > > > > > > >>> and
> > > > > > > > > >>> IE9+
> > > > > > > > > >>> (this
> > > > > > > > > >>> one
> > > > > > > > > >>> is already OK)
> > > > > > > > > >>> because of this feature?
> > > > > > > > > >>> 
> > > > > > > > > >>>> Now regarding its position:
> > > > > > > > > >>>> Rollover is good but not enough, we should somehow put
> > > > > > > > > >>>> it
> > > > > > > > > >>>> in
> > > > > > > > > >>>> the
> > > > > > > > > >>>> lower
> > > > > > > > > >>>> panel
> > > > > > > > > >>>> under general or even another tab - (live data).
> > > > > > > > > >>> 
> > > > > > > > > >>> This is a bit different requirement. The point of this
> > > > > > > > > >>> specific
> > > > > > > > > >>> is
> > > > > > > > > >>> to
> > > > > > > > > >>> give
> > > > > > > > > >>> a
> > > > > > > > > >>> better
> > > > > > > > > >>> overview in the main tab. If it will be done we can
> > > > > > > > > >>> decide
> > > > > > > > > >>> if
> > > > > > > > > >>> we
> > > > > > > > > >>> want
> > > > > > > > > >>> to
> > > > > > > > > >>> give
> > > > > > > > > >>> more
> > > > > > > > > >>> details in sub tabs.
> > > > > > > > > >>> 
> > > > > > > > > >>>> We could later on have a (live data Tab) in other places
> > > > > > > > > >>>> as
> > > > > > > > > >>>> well
> > > > > > > > > >>>> like
> > > > > > > > > >>>> host,
> > > > > > > > > >>>> cluster...
> > > > > > > > > >>>> Eldan
> > > > > > > > > >>> 
> > > > > > > > > >>> [1]: http://www.ovirt.org/Download
> > > > > > > > > >>> [2]: http://caniuse.com/#feat=canvas
> > > > > > > > > >>> 
> > > > > > > > > >>>> ----- Original Message -----
> > > > > > > > > >>>> From: "Einav Cohen" <ecohen at redhat.com>
> > > > > > > > > >>>> To: "Ewoud Kohl van Wijngaarden"
> > > > > > > > > >>>> <ewoud+ovirt at kohlvanwijngaarden.nl>
> > > > > > > > > >>>> Cc: "Alexander Wels" <awels at redhat.com>, "Eldan
> > > > > > > > > >>>> Hildesheim"
> > > > > > > > > >>>> <ehildesh at redhat.com>, engine-devel at ovirt.org, "info"
> > > > > > > > > >>>> <info at eldanet.com>
> > > > > > > > > >>>> Sent: Friday, November 8, 2013 10:50:10 PM
> > > > > > > > > >>>> Subject: Re: [Engine-devel] [UX] how to design a
> > > > > > > > > >>>> bar/line
> > > > > > > > > >>>> chart?
> > > > > > > > > >>>> 
> > > > > > > > > >>>>> ----- Original Message -----
> > > > > > > > > >>>>> From: "Ewoud Kohl van Wijngaarden"
> > > > > > > > > >>>>> <ewoud+ovirt at kohlvanwijngaarden.nl>
> > > > > > > > > >>>>> Sent: Thursday, November 7, 2013 11:44:07 AM
> > > > > > > > > >>>>> 
> > > > > > > > > >>>>> On Wed, Nov 06, 2013 at 11:45:36AM -0500, Alexander
> > > > > > > > > >>>>> Wels
> > > wrote:
> > > > > > > > > >>>>>> I suppose we need to answer a few questions before we
> > > > > > > > > >>>>>> can
> > > > > > > > > >>>>>> go
> > > > > > > > > >>>>>> into
> > > > > > > > > >>>>>> which
> > > > > > > > > >>>>>> library is better:
> > > > > > > > > >>>>>> 
> > > > > > > > > >>>>>> 1. Do we mind sending data over to Google so Google
> > > > > > > > > >>>>>> can
> > > > > > > > > >>>>>> render
> > > > > > > > > >>>>>> images
> > > > > > > > > >>>>>> for
> > > > > > > > > >>>>>> us.
> > > > > > > > > >>>>> 
> > > > > > > > > >>>>> I'd say no. Even from a reliability point of view since
> > > > > > > > > >>>>> users
> > > > > > > > > >>>>> may
> > > > > > > > > >>>>> have
> > > > > > > > > >>>>> systems that aren't connected to the internet.
> > > > > > > > > >>>> 
> > > > > > > > > >>>> +1
> > > > > > > > > >>>> 
> > > > > > > > > >>>>> (Though I don't know how well oVirt handles this
> > > > > > > > > >>>>> currently.)
> > > > > > > > > >>>> 
> > > > > > > > > >>>> AFAIK - oVirt is handling it ('it' ==  having no
> > > > > > > > > >>>> internet
> > > > > > > > > >>>> connection)
> > > > > > > > > >>>> well.
> > > > > > > > > >>>> _______________________________________________
> > > > > > > > > >>>> Engine-devel mailing list
> > > > > > > > > >>>> Engine-devel at ovirt.org
> > > > > > > > > >>>> http://lists.ovirt.org/mailman/listinfo/engine-devel
> > > > > > > > > >>> 
> > > > > > > > > >>> _______________________________________________
> > > > > > > > > >>> Engine-devel mailing list
> > > > > > > > > >>> Engine-devel at ovirt.org
> > > > > > > > > >>> http://lists.ovirt.org/mailman/listinfo/engine-devel
> > > > > > > > > >> 
> > > > > > > > > >> _______________________________________________
> > > > > > > > > >> Engine-devel mailing list
> > > > > > > > > >> Engine-devel at ovirt.org
> > > > > > > > > >> http://lists.ovirt.org/mailman/listinfo/engine-devel
> > > > > > > > 
> > > > > > > > _______________________________________________
> > > > > > > > Engine-devel mailing list
> > > > > > > > Engine-devel at ovirt.org
> > > > > > > > http://lists.ovirt.org/mailman/listinfo/engine-devel
> > > 
> > > 
> > _______________________________________________
> > Engine-devel mailing list
> > Engine-devel at ovirt.org
> > http://lists.ovirt.org/mailman/listinfo/engine-devel
> > 
> _______________________________________________
> Engine-devel mailing list
> Engine-devel at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/engine-devel
> 
> 
>

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