Zentyal dashboard slow and unresponsive [SOLVED]

[Squirrel]

Hi,

I guess there have been other threads about the same problem, but didnt find any solution to a problem that was similar to mine, so here it is! Sorry if this is an duplicate of another thread.

I have used zentyal since the beta of 3.0, and the web-interface has always been alittle slow (10 sec delay sometimes), but I've had no problems to cope with it.
Yesterday, I did an update of zentyal and system packages. I tell you, in my experience, updating zentyal is like russian roulette. I rarely notice any improvements, but new bugs rarely go unnoticed. (ofc, we can all blame my incompetence for that!)

But anyways, yesterday I decided to update. Haven't done that in 3 months. I regret i didn't wait 4 months. 
Symptoms:
So, now the web interface is really sluggish! We're talking about 30-60 seconds just to log in. Suddenly, I can navigate different parts of the interface with no problems, really quick and snappy, quicker than before, almost instantly. But then at some point, I press the "Dashboard" link, and we're back to waiting 60-120 seconds for the page. After the dashboard-page finally appear, the statistics there refreshes in 10 seconds, and then, the entire dashboard-page freezes. Can't right-click anything, can't mark any text, nothing. Firefox works fine at the same time in other tabs. After about 30-60 seconds, the dashboard statistics refreshes again, and the page is suddenly responsive again, and I can navigate further (with some more waiting).

I've tested on multiple computers, and restarted the server. Running on a Primergy tx120. top shows no activity whatsoever while i wait for the refresh, or during the freeze.

I would really appreciate some help on this matter!

Regards
Squirrel

[Squirrel]

Found a workaround:
Unregister the server from zentyal cloud. Work like it should now. 

[otoh]

Did that definitely solve the problem? I'm getting the same issue but I don't have the server registered on Zentyal (and don't even have the cloud client module installed).

Sometimes it takes eg a minute to log in - my browser generally times out. During which time, other services - mail, web, ssh, etc, are all working as expected. Once I get in, then it tends to be quick again. Sometimes if it won't log in, specifying a further URL, eg /Network/Diag will kick it into action. But it is getting annoying!

Are there any config parameters we can change on the dashboard service? Or is there a way of restarting it if it gets bogged down?

[fatbob]

I see the same if I connect to the server over a vpn. The dashboard very seldom loads. I work around it by going to another page directly first. Its just the dashboard thats screwed. However once I'm in at another page I can usually jump to the dashboard

[half_life]

If you are having sluggish server issues it is time to consult the command prompt to get to the bottom of things.  On a command prompt use the top command to get a sense of which processes are hogging CPU.  You can also get an indication if it is I/O related.  Lastly restarting the web interface and (sometimes necessary) web server will normally get things back on track.  I haven't observed this problem with the 3.X series but did see it regularly with the 2.X series.  For me it turned out to be a thrashing mysql instance.

To restart the web interface

Code: [Select]

/etc/init.d/zentyal webserver restart
To restart the web server

Code: [Select]

/etc/init.d/zentyal apache2 restart
I have most modules installed on my system here (3.0.17) patched and up to date.  Very snappy.  It is notable that this is a virtual machine under Proxmox with moderate resources. (home server)

The work Zentyal install is similar with the differences being a clustered Proxmox setup with much larger servers.  This is a 2.2.7 install if memory serves.

[otoh]

If you are having sluggish server issues it is time to consult the command prompt to get to the bottom of things.  On a command prompt use the top command to get a sense of which processes are hogging CPU. 

Thanks for the reply. The weird thing is that I have used top and nothing is hogging the CPU - my system load is low, eg 0.2, and even while waiting for the dashboard to load, nothing reports a high CPU use.

Unlike fatbob, I'm not connecting via a VPN, but over the internet; I have a (hardware) firewall allowing the relevant port through. But I have seen the issue even when connecting locally. And like fatbob, if I manually try another URL in the web GUI, it usually catches up; after which it is quick - even the dashboard.

So It's not a disaster - just annoying. But thanks for letting me know how to restart the web interface - next time I will give that a go!

[fatbob]

Yes indeed it's not a resource issue by any means, the server bairly notices and this is a bare metal install rather then virtual (not that it would make much difference). When accesing the admin site locally it is reasonably fine.  The only delay is over the vpn. I should point out that the connection to the zarafa web site over the same link is instant, ftp transfers are alos pretty snappy. So the problem is definatly with the administration site. Server restarts, full reboot, or service restarts, have not effect on the issue.

I suspect the issue may have something to do with the automatic refreshing that takes place on that page.

[Sam Graf]

Just want to point out that it's not a universal experience. Over the years and across versions the "slow GUI" problem has popped up from time to time, but since not everybody experiences it, to my recollection no one has ever established a definitive cause.

[otoh]

Just want to point out that it's not a universal experience. Over the years and across versions the "slow GUI" problem has popped up from time to time, but since not everybody experiences it, to my recollection no one has ever established a definitive cause.

Both good and annoying to know it's not everyone I have almost the exact same experience as fatbob - other than that I am not VPNing, only connecting in remotely. Everything else is quick - FTP/HTTP/SSH etc.

I suspect the issue may have something to do with the automatic refreshing that takes place on that page.

It could be - but once I'm in, the dashboard seems to work fine - I think you said the same?

Oh well - it's not a disaster and Zentyal is still awesome stuff which has saved me a lot of time But if we could figure it out, it would be even better - I'll tinker a bit and report back!

[Sam Graf]

Just to add to the possibilities, I have an old server (powered by dual PIIIs, if that tells you anything about its age) that i use for testing purposes. On that server, because it is slow, I can see that on first enterining the dashboard an update check is running. That takes quite a while to finish. Obviously that doesn't happen after the dashboard is fully up. Maybe a connection?

[fatbob]

Ah having experimented a bit this seems quite browser specific.

On windows 7 sp1

it's slow in chrome  v26.0.1410.43 m

It's fast in firefox 19.0.2
It's fast in IE 9

So this would indicate it's a browser incompatibility with the client side code in the site. Which explains why it exhibits itself on the dashboard page. It must have js call backs to updated the network usage / software updates and other panels.

otoh - can you check with some different browsers and feed back. It might be a re creatable bug.

[Sam Graf]

On windows 7 sp1
...
It's fast in IE 9

So this would indicate it's a browser incompatibility...

IE 10 works as expected as well. As does Safari for iOS. I need to confirm about Opera (and Epiphany, while I'm at it) under Debian 6, but my recollection is that it works fine as well.

So I think it's premature to declare a "browser incompatibility," since we may have at most, so far, only Chrome misbehaving? I can't confirm that since I don't use either Chrome or Chromium.

[Sam Graf]

OK, am testing Opera and Epiphany under Debian 6 on a VPN connection. The computer is an HP Compaq nx6125 laptop powered by an AMD Turion 64 Mobile ML-40. The Zentyal GUI is not fast, but all page loads are about the same. Epiphany is probably the faster of the two browsers.

For what it's worth...

[fatbob]

I'll try it in chrome on another couple of machines when I'm on site tomorrow

[otoh]

I concur that it seems to be a Chrome issue - as I'm a web developer, am feeling a bit sheepish about not having thought of it! But this is the first time I've ever seen anything that specifically doesn't like Chrome. I tried:

* Remotely, over the internet through a firewall: Chrome, Chrome Incognito (to rule out any cache/cookie issues), Firefox, IE10
* Locally, VNCing into a machine on the same network: Chrome & Safari

It seems to be specifically Chrome over the internet; other combinations work. My internet connection is relatively quick, but still slower than the LAN, so maybe it's the speed; or possibly a going-through-a-firewall issue. Symptoms:

* Initial login screen loads quickly
* Then when logging in, following dashboard page is very slow; browser times out either completely, or shows partial page with no CSS
* Manually changing the URL to another page in Zentyal sometimes makes it catch up; sometimes not

Interestingly, when using Safari, the login screen warns me that I should be using Firefox as it's the only officially supported browser. I don't see this warning in Chrome or IE.