What settings for maximum speed on a large configuration ?

[Monarobase]

Hello,

I've recently installed litespeed on our pre production server and when I get all the issues sorted out I will be transfering quite alot of accounts from a smaller server running Apache to this new server.

I've read in various places that setting some options too high will slow things down instead of speeding things up.

Our customers host various scripts (Wordpress, Joomla, PhpBB, vBulletin, IPB and also custom scripts, some better optimised then others).

We're aiming at getting the best performance and stability for our customers websites.

Our server has got 256GB of RAM and 32 * 3.1GHz threads.

I've already activated and configured Xcache 3.0.1 and allowed it 1GB of cache space…

I've run some tests and seem to be getting 503 error messages when there are too many processes being run. By upping LSAPI Max connections and LSAPI_Children from 35 to 400 most of the errors have gone.

I want this server to be able to cope with a large number of simultaneous requests and serve each of them quickly. I want to try and get the configuration right before migrating the accounts to it.

Can you guide me to have the right settings for maximum performance and maximum number of processes ? Shoud I pay to have you configure these settings ? Can you do this with only a few customers on the server ?

I've been monitoring the performance of a small php script with echo "hello world" from different locations and have been getting spikes every now and again.

Most of the time the scripts download in 15 to 17ms and then every now and again the latency goes over 500ms…

This server has only got a few medium traffic sites on it so it should be stable and have regular latency times. I'm worried that if I get 503 errors and latency spikes what it will be like with 700 or 800 accounts on the server.

The server load is always below 1.5 for the mement, this includes MySQL and other services so I don't think I'm being limited by the 2 Core test licence… am I ?

Thanks

 

[Monarobase]

Also Monarobase - haven't you consider putting LSPHP to separate machine/s just for redundancy/scalability ?

What do you mean exactly by this ? Activate Litespeed loadbalancer ?

Or have a NAS shared by two servers ?

Or something else ?

 

[Monarobase]

We would have to test the speed to see what the extra network would add…

I'm not sure about a reliability difference as if you don't also have the web server then the PHP scripts alone won't be and it seems that you would be adding another point of failure unless you can automaticaly share all PHP processes between both servers.

The first thing we would move would by MySQL to create a multiple server cluster. We've alread clustered DNS servers but that doesn't use much ressources.

The server we're currently trying to get running smoothly with litespeed has more than 5 times CPU than our previous server and 10 times more memory so with the right software and settings we should be able to hold out quite some time on the new server configuration.

If you're using a NAS for the files, why not go the whole way with a load balancer ?

 

[webizen]

I'm also in a position simmilar to Monarobase's. We are planning to migrate to Litespeed with hundreds of accounts, thousands of domains. Please advice how to avoid 503 errors and which parameters are most important in shared enviroment?

...

https://store.litespeedtech.com/store/knowledgebase.php?action=displayarticle&id=31

 

[Monarobase]

Hello,

I've read the article, I'm getting 503 error messages and have actived core dumps but am not getting core dumps when I get the 503 error message.

I've checked my logs and it seems to happen when /scripts/restartsrv_httpd is run.

I'm watching to see if this is the problem, if it is I will ask you for some advice about making this script do a gracefull restart of litespeed instead of completly restarting litespeed and all php children.

cPanel runs this script by default for each account when it rotates logs so it's important that litespeed is reloaded without causing 503 errors.


Here is the type of errors I'm seeing :

2013-01-22 08:22:42.168 [INFO] [XX.XX.XX.XX:51376-1#APVH_my_domain.com] connection to [uds://tmp/lshttpd/lsphp5.sock.687671] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-22 08:22:42.175 [INFO] [XX.XX.XX.XX:51376-1#APVH_my_domain.com] connection to [uds://tmp/lshttpd/lsphp5.sock.687671] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-22 08:22:42.183 [INFO] [XX.XX.XX.XX:51376-1#APVH_my_domain.com] connection to [uds://tmp/lshttpd/lsphp5.sock.687671] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-22 08:22:42.183 [NOTICE] [XX.XX.XX.XX:51376-1#APVH_my_domain.com] Max retries has been reached, 503!
2013-01-22 08:22:42.183 [NOTICE] [XX.XX.XX.XX:51376-1#APVH_my_domain.com] oops! 503 Service Unavailable

 

[Monarobase]

Ok I've been watching the server logs all morining. I've had multiple error 503's and everytime a second or too before I have something like this :

2013-01-22 12:07:04.347 [NOTICE] Server Restart Request via Signal...
2013-01-22 12:07:04.347 [NOTICE] [PID: 777249]: start cgid: 878637, /usr/local/lsws/bin/lscgid
2013-01-22 12:07:04.347 [NOTICE] [Child: 777254] Start shutting down gracefully ...
2013-01-22 12:07:04.347 [NOTICE] [Child: 777255] Start shutting down gracefully ...

So I'm glad it's not actually something crashing but I cannot have 503 erros on my customers websites everytime cPanel requests a reload for Apache or Litespeed is gracefully restarted.

What can I do to stop this from happening ?

 

[NiteWave]

graceful restart will cause 503 error --- this is a good point, and new to me. usually 503 error is random and not easy to reproduce. not sure if you can work out a simple test case which we can reproduce it in our lab so we can proceed.

 

[Monarobase]

I'll have to check my logs, but I was wandering if the restart wasn't a symptom instead of a cause.

Could it be PHP hitting litespeed's CPU limit ?

I upped it from the default 80% to 800% yesterday but haven't had a chance to check the logs yet.

I get a 503 error when litespeed can't access PHP. Over the last 20 times in the past two days users got 503 errors I see litespeed doing a gracefull restart then a few seconds later litespeed says it tried to access PHP 3 times and didn't get an answer so it shows a 503 error message.

I'll check later today and see if the new CPU limit has solved the 503 error messages or not

 

[Monarobase]

Here is a section of the logs :

2013-01-23 10:10:24.000 [NOTICE] Server Restart Request via Signal...
2013-01-23 10:10:24.000 [NOTICE] [PID: 582321]: start cgid: 619120, /usr/local/lsws/bin/lscgid
2013-01-23 10:10:24.000 [INFO] Pass listener 127.0.0.1:443.
2013-01-23 10:10:24.000 [INFO] Pass listener 127.0.0.1:80.
2013-01-23 10:10:24.000 [INFO] Pass listener IP1.XX.XX.XX:443.
2013-01-23 10:10:24.000 [INFO] Pass listener IP1.XX.XX.XX:80.
2013-01-23 10:10:24.000 [INFO] Pass listener *:7080.
2013-01-23 10:10:24.001 [NOTICE] [Child: 582326] Start shutting down gracefully ...
2013-01-23 10:10:24.001 [NOTICE] [Child: 582325] Start shutting down gracefully ...
2013-01-23 10:10:24.001 [INFO] Stop listener 127.0.0.1:443.
2013-01-23 10:10:24.001 [INFO] Stop listener 127.0.0.1:80.
2013-01-23 10:10:24.001 [INFO] Stop listener IP1.XX.XX.XX:443.
2013-01-23 10:10:24.001 [INFO] Stop listener IP1.XX.XX.XX:80.
2013-01-23 10:10:24.001 [INFO] Stop listener *:7080.
2013-01-23 10:10:24.032 [NOTICE] Your License key will expire in 10 days
2013-01-23 10:10:24.032 [NOTICE] Loading LiteSpeed/4.2.1 Enterprise ...
2013-01-23 10:10:24.033 [NOTICE] [ADMIN] server socket: uds://usr/local/lsws/admin/tmp/admin.sock.7318
2013-01-23 10:10:24.033 [NOTICE] Loading configuration from /usr/local/lsws/conf/httpd_config.xml ...
2013-01-23 10:10:24.035 [NOTICE] Recovering server socket: [127.0.0.1:443]
2013-01-23 10:10:24.035 [NOTICE] Recovering server socket: [127.0.0.1:80]
2013-01-23 10:10:24.036 [NOTICE] Recovering server socket: [IP1.XX.XX.XX:443]
2013-01-23 10:10:24.036 [NOTICE] Recovering server socket: [IP1.XX.XX.XX:80]
2013-01-23 10:10:24.036 [NOTICE] Recovering server socket: [*:7080]
2013-01-23 10:10:24.036 [NOTICE] [config] chroot is disabled.
2013-01-23 10:10:24.036 [INFO] old priority: 0, new priority: 0
2013-01-23 10:10:24.036 [INFO] [config:server:basic] For better obscurity, server version number is hidden in the response header.
2013-01-23 10:10:24.039 [NOTICE] [PID: 619137]: start cgid: 619138, /usr/local/lsws/bin/httpd
2013-01-23 10:10:24.039 [NOTICE] The maximum number of file descriptor limit is set to 15000.
2013-01-23 10:10:24.055 [NOTICE] [config:server:epsr:lsphp4]'Process Limit' probably is too low, adjust the limit to: 310.
2013-01-23 10:10:24.055 [WARN] [config:server:rails] Cannot find ruby interpreter, Rails easy configuration is turned off
2013-01-23 10:10:24.055 [INFO] Processing config file: /usr/local/apache/conf/includes/pre_main_global.conf
2013-01-23 10:10:24.055 [INFO] Processing config file: /usr/local/apache/conf/includes/pre_main_2.conf
2013-01-23 10:10:24.055 [INFO] Processing config directory: /etc/httpd/conf.d
2013-01-23 10:10:24.055 [INFO] Processing config file: /etc/httpd/conf.d/000_mod_sed.conf
2013-01-23 10:10:24.055 [INFO] Processing config file: /etc/httpd/conf.d/mod_evasive.conf
2013-01-23 10:10:24.055 [INFO] Processing config file: /usr/local/apache/conf/modhostinglimits.conf
2013-01-23 10:10:24.055 [INFO] Processing config file: /usr/local/apache/conf/php.conf
2013-01-23 10:10:24.055 [INFO] Processing config file: /usr/local/apache/conf/includes/errordocument.conf
2013-01-23 10:10:24.088 [INFO] Processing config file: /usr/local/apache/conf/includes/pre_virtualhost_global.conf
2013-01-23 10:10:24.088 [INFO] Processing config file: /usr/local/apache/conf/includes/pre_virtualhost_global.conf
2013-01-23 10:10:24.088 [INFO] Processing config file: /usr/local/apache/conf/includes/pre_virtualhost_2.conf
2013-01-23 10:10:24.088 [INFO] Processing config file: /usr/local/apache/conf/includes/pre_virtualhost_2.conf
2013-01-23 10:10:24.089 [INFO] Processing config file: /usr/local/apache/conf/includes/post_virtualhost_global.conf
2013-01-23 10:10:24.089 [INFO] Processing config file: /usr/local/apache/conf/includes/post_virtualhost_global.conf
2013-01-23 10:10:24.089 [INFO] Processing config file: /usr/local/apache/conf/includes/post_virtualhost_2.conf
2013-01-23 10:10:24.089 [INFO] Processing config file: /usr/local/apache/conf/includes/post_virtualhost_2.conf
2013-01-23 10:10:24.108 [NOTICE] litespeed (619137) is ready
2013-01-23 10:10:24.108 [NOTICE] [AutoRestarter] new child process with pid=619141 is forked!
2013-01-23 10:10:24.108 [NOTICE] [AutoRestarter] new child process with pid=619142 is forked!
2013-01-23 10:10:24.108 [INFO] Stop listener 127.0.0.1:443.
2013-01-23 10:10:24.108 [INFO] Stop listener 127.0.0.1:80.
2013-01-23 10:10:24.108 [INFO] Stop listener IP1.XX.XX.XX:443.
2013-01-23 10:10:24.108 [INFO] Stop listener IP1.XX.XX.XX:80.
2013-01-23 10:10:24.108 [INFO] Stop listener IP2.XX.XX.XX:443.
2013-01-23 10:10:24.109 [INFO] Stop listener *:7080.
2013-01-23 10:10:24.109 [INFO] Stop listener IP2.XX.XX.XX:80.
2013-01-23 10:10:24.109 [NOTICE] [Child: 619142] Setup swapping space...
2013-01-23 10:10:24.109 [NOTICE] [Child: 619141] Setup swapping space...
2013-01-23 10:10:24.109 [NOTICE] [child: 619142] Successfully change current user to nobody
2013-01-23 10:10:24.109 [NOTICE] [Child: 619142] Core dump is enabled.
2013-01-23 10:10:24.109 [NOTICE] [child: 619141] Successfully change current user to nobody
2013-01-23 10:10:24.109 [NOTICE] [Child: 619141] Core dump is enabled.
2013-01-23 10:10:24.109 [NOTICE] [Child: 619142] LiteSpeed/4.2.1 Enterprise starts successfully!
2013-01-23 10:10:24.110 [NOTICE] [Child: 619141] LiteSpeed/4.2.1 Enterprise starts successfully!
2013-01-23 10:10:24.191 [NOTICE] New litespeed process is ready, litespeed (582325) stops listeners
2013-01-23 10:10:24.191 [INFO] Stop listener 127.0.0.1:443.
2013-01-23 10:10:24.191 [INFO] Stop listener 127.0.0.1:80.
2013-01-23 10:10:24.191 [INFO] Stop listener IP1.XX.XX.XX:443.
2013-01-23 10:10:24.191 [INFO] Stop listener IP1.XX.XX.XX:80.
2013-01-23 10:10:24.191 [INFO] Stop listener *:7080.
2013-01-23 10:10:24.202 [NOTICE] New litespeed process is ready, litespeed (582326) stops listeners
2013-01-23 10:10:24.202 [INFO] Stop listener IP2.XX.XX.XX:443.
2013-01-23 10:10:24.202 [INFO] Stop listener IP2.XX.XX.XX:80.
2013-01-23 10:10:24.202 [NOTICE] [Child: 582326] Shut down successfully! 
2013-01-23 10:10:24.211 [NOTICE] [AutoRestarter] cleanup children processes and unix sockets of process with pid=582326 !
2013-01-23 10:10:24.311 [NOTICE] [AutoRestarter] child process with pid=582326 exited with status=0!
2013-01-23 10:10:24.857 [INFO] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.582321] on request #13, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-23 10:10:24.866 [INFO] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.582321] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-23 10:10:24.874 [INFO] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.582321] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-23 10:10:24.874 [NOTICE] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] Max retries has been reached, 503!
2013-01-23 10:10:24.874 [NOTICE] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] oops! 503 Service Unavailable
2013-01-23 10:10:24.874 [NOTICE] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] Content len: 0, Request line: 'GET /download/file.php?id=20060&sid=DWNURL HTTP/1.1'
2013-01-23 10:10:24.874 [INFO] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] Cookie len: 84, phpbb3_igyxp_u=1; phpbb3_igyxp_k=; COOKIE_CONTENTS_1
2013-01-23 10:10:24.874 [INFO] [IPCIENT1.XX.XX.XX:34563-1#APVH_domain.tld] File not found [/home/USER1/public_html/503.shtml] 
2013-01-23 10:10:25.133 [INFO] [HTAccess] Updating configuration from [/home/USER1/public_html/.htaccess]
2013-01-23 10:10:25.200 [NOTICE] [AutoUpdate] Checking for new releases..., pid=619152
2013-01-23 10:10:25.200 [NOTICE] Start to clean up cache directory, pid=619153
2013-01-23 10:10:25.478 [INFO] [AutoUpdate] No new update.
2013-01-23 10:10:26.609 [INFO] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.582321] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-23 10:10:26.618 [INFO] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.582321] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-23 10:10:26.626 [INFO] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.582321] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!
2013-01-23 10:10:26.626 [NOTICE] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] Max retries has been reached, 503!
2013-01-23 10:10:26.626 [NOTICE] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] oops! 503 Service Unavailable
2013-01-23 10:10:26.626 [NOTICE] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] Content len: 0, Request line: 'GET /download/file.php?avatar=2215_1331283561.jpg HTTP/1.1'
2013-01-23 10:10:26.626 [INFO] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] Cookie len: 84, phpbb3_igyxp_u=1; phpbb3_igyxp_k=; COOKIE_CONTENTS_1
2013-01-23 10:10:26.626 [INFO] [IPCIENT1.XX.XX.XX:34561-4#APVH_domain.tld] File not found [/home/USER1/public_html/503.shtml]

Every 503 error looks like this with :

First : "[NOTICE] Server Restart Request via Signal..."

Second : "[Child: XXXXX] Start shutting down gracefully ..." third the "[NOTICE] New litespeed process is ready, litespeed (582325) stops listeners"

Then "[INFO] [IPCIENT2.XX.XX.XX:34556-16#APVH_domain.tld:lsapi] connection to [uds://tmp/lshttpd/lsphp5.sock.XXXXX] on request #0, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!"

And finaly "[NOTICE] [IPCIENT1.XX.XX.XX:34558-8#APVH_domain.tld] Max retries has been reached, 503!"

 

[NiteWave]

searched out a related thread:
http://www.litespeedtech.com/support/forum/showthread.php?t=6186

looks the restart not from graceful restart, but from cPanel.

 

[Monarobase]

I get the same 503 erros when I run a gracefull restart from the litespeed web admin pannel.

I haven't got restarts every 20 minutes like in that topic.

I can't have 503 errors every time a client adds a subdomain…

The problem here is not what is causing the gracefull restart but why PHP becomes unavailable for almost 10 seconds just after the gracefull restart.

I don't think a gracefull restart shouldn't affect PHP processes… I've got the impression that litespeed restarts then asks all PHP children to restart and during the time it takes PHP to restart all children Litespeed gives out 503 errors because it can't connect to PHP.

I've only got 5 production sites on this server, my guess is it could take longer to restart all PHP processes when there are alot more children…

Could this be a setting or a bug with LSAPI PHP Suexec in deamon mode ?

Litespeed is sending a call to a PHP process that doesn't exist anymore because it has been restarted.

Where would I look to find out if it's a bad setting ?

 

[Monarobase]

Here's the output of the restarts log :

[root@newns10 demo]# cat /usr/local/lsws/logs/ap_cmd_param.log | grep "Wed Jan 23"
Wed Jan 23 00:09:35 CET 2013: -k graceful
Wed Jan 23 00:20:46 CET 2013: -l
Wed Jan 23 00:20:46 CET 2013: -V
Wed Jan 23 00:20:46 CET 2013: -v
Wed Jan 23 00:20:46 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work.yA_74YWLDRc4N0NO
Wed Jan 23 00:20:47 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work.yA_74YWLDRc4N0NO
Wed Jan 23 01:22:16 CET 2013: -v
Wed Jan 23 01:22:17 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work._X5VOBfoiKV2D8lh
Wed Jan 23 01:22:17 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work._X5VOBfoiKV2D8lh
Wed Jan 23 01:25:01 CET 2013: -v
Wed Jan 23 01:25:02 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work.458t5scsOzSeAxAh
Wed Jan 23 01:25:02 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work.458t5scsOzSeAxAh
Wed Jan 23 01:49:47 CET 2013: -l
Wed Jan 23 01:49:47 CET 2013: -V
Wed Jan 23 01:49:48 CET 2013: -v
Wed Jan 23 01:49:48 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work.qWUK8ZWGJS6bRV2K
Wed Jan 23 01:49:49 CET 2013: -DSSL -t -f /usr/local/apache/conf/httpd.conf.work.qWUK8ZWGJS6bRV2K
Wed Jan 23 02:06:24 CET 2013: -k graceful
Wed Jan 23 02:22:25 CET 2013: -v
Wed Jan 23 04:03:14 CET 2013: -k graceful
Wed Jan 23 06:00:04 CET 2013: -k graceful
Wed Jan 23 08:13:34 CET 2013: -k graceful
Wed Jan 23 10:10:22 CET 2013: -k graceful
Wed Jan 23 12:07:12 CET 2013: -k graceful
Wed Jan 23 13:05:59 CET 2013: -k graceful

As you can see there is nothing abnormal about the number of restarts. It's just the 503 error messages that happen a few seconds after every restart that are the problem.

 

[NiteWave]

have you touched following default setting ?
Server->General->Graceful Restart Timeout (secs)

 

[Monarobase]

I've got this :

Auto Restart : Yes
Auto Fix 503 Error : Yes
Graceful Restart Timeout (secs) : 120

The gracefull restart of litespeed is done with a few seconds. I'm pretty sure I did not touch this setting even though it says the default is 300.

I don't think I'm hitting the 120 second timeout as the whole procedure takes less than 20 seconds before PHP comes back.

 

[Monarobase]

Hello,

As I'm still quite new to Litespeed, is fixing this issue included in the free forum support or should I pay to have this fixed ?

What's the difference between paid and forum support ? Is it just the response time or the whole level of intervention ?

I ask this because with some companies I've tried to work with they didn't tell me when the question I asked was too complicated for free support and I had to wait a long time and insist alot before being told I had to pay to get an answer.

I don't mind it taking a few extra days by the forum although I've only got 7 more days trial and need this to be fixed before purchasing the paid licence.

Thanks

 

[NiteWave]

this issue is not a known issue, so I don't reply you at once.

Could this be a setting or a bug with LSAPI PHP Suexec in deamon mode ?

this looks a nice clue and I actually did simple tests in daemon mode, tried to reproduce 503 error --- but failed.

not sure if it's ok for you to run short time tests on your production server.
e.g., switch to non-daemon mode, restart, see if 503 still happen. or disable xcache temporarily and test if no 503.

another good way to strace lsphp5 process, to catch the 503 when it happens.

in debug's point of view, it's good you can easily reproduce 503 error(by graceful restart) in current environment.

also, please give a screen shot of lsphp5 settings, see if we can give any advice, which may avoid or reduce 503 error.

 

[Monarobase]

Hello,

I've run the tests,

I haven't been able to reproduce this with Suexec deamon deactivated and Xcache enabled, or with Suexec deamon activated and Xcache disabled.

To get a 503 error you have to be running a php instance at the right moment.

To reproduce this I run a gracefull restart and as fast as possible reload a web php using PHP multiple times.

Out of 10 tries I managed 5 503 error messages with Suexec deamon + Xcache 3.0.1.

Should I try Xcache 2 and disable varibale cache or is there a way to debug why this happens with Xcache 3.0.1 ?

It rearly makes sense to be able to allow variable cache… and it's stable so long as there isn't a gracefull restart.

 

[Monarobase]

Here's the screenshot of my PHP settings :

Thanks

 

[NiteWave]

the settings looks normal except
Retry Timeout(secs), usually I leave it to default 0.

I think we've got some progress by your tests. so the 503 error is narrowed down to "Suexec deamon + Xcache 3.0.1" combination only and 50% possibility to happen.

Should I try Xcache 2 and disable varibale cache or is there a way to debug why this happens with Xcache 3.0.1 ?

yes, I think this is the right path to go. since xcache looks being actively developed, you may submit a bug report to them, and they may instruct you the best way how to debug xcache.

 

[Monarobase]

I changed the 0 to 1s in the hope that when PHP was not accessible it would wait long enough to let PHP startup.

The 50% chance is only because I didn't reload the page at exactly the right time.

I think I need to understand exactly what is happenning before contacting xcache.

From my logs I see :
2013-01-25 00:09:46.980 [NOTICE] Server Restart Request via Signal...
2013-01-25 00:09:46.981 [NOTICE] [PID: 772009]: start cgid: 807475, /usr/local/lsws/bin/lscgid
2013-01-25 00:09:46.981 [NOTICE] [Child: 772013] Start shutting down gracefully ...
2013-01-25 00:09:46.981 [NOTICE] [Child: 772014] Start shutting down gracefully ...
[...]
2013-01-25 00:09:47.230 [NOTICE] New litespeed process is ready, litespeed (772013) stops listeners

then :

2013-01-25 00:09:47.232 [INFO] [IPADR:35426-18#APVH_domain.tld] connection to [uds://tmp/lshttpd/lsphp5.sock.772009] on request #7, confirmed, 1, associated process: -1, running: 0, error: Connection reset by peer!

multiple times

then

2013-01-25 00:10:01.397 [NOTICE] [Child: 772013] Shut down successfully!
2013-01-25 00:10:01.408 [NOTICE] [AutoRestarter] cleanup children processes and unix sockets of process with pid=772013 !
2013-01-25 00:10:01.508 [NOTICE] [AutoRestarter] child process with pid=772013 exited with status=0!
2013-01-25 00:10:01.508 [NOTICE] [PID:772009] Server Stopped!

After that everything goes back to normal

It seems that litespped fails to load a new server but when litespeed shuts it down everything works again