Bitrix admin panel crashes. Where can I see the error?

Question

Apache HTTP Server

When you try to enter the "platform update" in the Marketplace, the site crashes. Tightly. in error.log I get

[Thu Feb 02 11:32:43.799757 2017] [proxy_fcgi:error] [pid 21684:tid 140648250283776] (70007)The timeout specified has expired: [client 94.37.650.238:41498] AH01075: Error dispatching request to :, referer: http://site.ru/bitrix/admin/perfmon_hit_grouped.php?lang=ru
[Thu Feb 02 11:33:31.472344 2017] [proxy_fcgi:error] [pid 21585:tid 140648300640000] (70007)The timeout specified has expired: [client 92.21.250.238:49040] AH01075: Error dispatching request to :

For some time it lies before error 503, then it recovers itself. What is the correct way to see where something broke?

Answer 1

By the way, one of the search methods is taken from the ticket:

In php.ini enable debugging:

xdebug.collect_params=3 
xdebug.trace_output_name=trace.%s.%R.%r.xt 
xdebug.trace_output_dir=/tmp/xdebug 
xdebug.auto_trace = 0

Then you need to create a folder /tmp/xdebug and make sure that the web server process has permission to write to it (or specify another one).
Then paste the xdebug_start_trace () line into the /bitrix/php_interface/dbconn.php file and repeat the operation.
Then give us the files created in the /tmp/xdebug folder
You can look for yourself, there is step by step everything that is performed by the script.

Answer 2

Did you happen to rename any module in the /bitrix/modules folder?
Try removing all left modules from /bitrix/modules. Directly transfer from there all directories of modules that you do not like temporarily to another folder. If it works, return one at a time.