[X2go-Dev] 3.99 Testing - General sluggishness

[John A. Sullivan III]

On Fri, 2011-07-22 at 00:26 -0400, John A. Sullivan III wrote: 
> I suppose I'll cover this one next as John Williams raised one of the
> issues.  This is another Windows only issue.
> 
> This issue has two categories.  It is complicated by the packing problem
> because we can only run the Windows client now with sub-optimal packing
> but it was a problem before the corruption issue struck.
> 
> Screen painting is just slower - not just a little slower - a lot
> slower.  The typical anecdotal test I've been using is scrolling through
> my Evolution Inbox.  Evolution has always seemed to have terrible
> graphics handling. I don't know what it does but it is always sluggish
> and awkward - thus an excellent test of how well we handle challenging
> graphics.
> 
> Even under Linux on a LAN, scrolling is miserably slow.  Shift down
> arrow and wait 1/4 second for a response.  This is really annoying.
> However, in Windows, it is wait 1/2 to 3/4 seconds for a response.  This
> takes it from annoying to dangerous as users wind up deleting or opening
> unintended emails, i.e., the hold the shift down arrow until they think
> they have highlighted the mails they want and then press enter.  What
> they don't realize is that five more emails will be selected because of
> the delay between what they see and the key buffer.
> 
> The other problem is a show stopper but I'm not sure it is an X2Go
> issue.  I think this is the same issue John Williams is seeing.  We see
> it only in Windows and Iceweasel.  It appears that Iceweasel hangs for
> quite a long time - not just a few seconds.  My guess is 30 seconds to a
> minute or more.  The system is really not hung.  All other applications
> work fine and the screen paints normally.  It is just the Iceweasel
> screen which does not paint.  Then, all at once, all the keystrokes and
> clicks are suddenly executed.  It's as if the events are being buffered
> or stored and not sent.
> 
> Although we cannot rule it out, we think we have only seen this in a
> single scenario - when using the Zimbra web client chat feature.  All
> other browsing and multi-tab activity seems to be fine but, as soon as
> someone sends me a chat message, Iceweasel painting stops . . . some of
> the time.  Other times it works perfectly fine.  Once, it gave me a
> white screen of death. Another time, it completely killed vcxsrv.  Most
> of the time, it causes this event execution delay.  I can merrily go and
> use other applications and all events are processed with no noticeable
> delay; I just can use Iceweasel. Then, everything catches up, all the
> events are processed, and all is well with the world once again.
> 
> Zimbra is a heavy AJAX application.  I don't know if the application
> John Williams is using is also heavily AJAX driven - John
> 
> _<snip>
I can confirm that the browser problem ONLY happens when using X2Go.  I
was able to run for quite a long time in Windows only chatting away on
the Zimbra web client chat service.  Not a single problem or delay. It
is nearly unusable under X2Go - John