Nginx – php-fpm error logging with nginx

loggingnginxphp-fpm

I have nginx+php-fpm on a server and the messages get truncated at 2048 chars, rendering the message quite unhelpful when a stack trace is logged : I can't see the following fields anymore:

host (not interesting)
upstream (not interesting)
request (very very interesting)
server (not interesting)
client (not interesting, always 127.0.0.1 because of our architecture)

How do you overcome this problem? Do you change the format? Or did you find a way to overcome this stupid 2048 chars limitation which I hear is hardcoded? Or to disable this backtrace?

Best Answer

It’s really hardcoded, you would have to edit the source file and compile nginx yourself. Have a look at the following file from the nginx source repository: http://trac.nginx.org/nginx/browser/nginx/trunk/src/core/ngx_log.h#L67

#define NGX_MAX_ERROR_STR   2048

Increase it to what suites your needs.

Related Solutions

Nginx – How to restart php-fpm

Note: prepend sudo if not root

Using SysV Init scripts directly:

/etc/init.d/php-fpm restart    # typical
/etc/init.d/php5-fpm restart   # debian-style
/etc/init.d/php7.0-fpm restart # debian-style PHP 7

Using service wrapper script

service php-fpm restart    # typical
service php5-fpm restart   # debian-style
service php7.0-fpm restart # debian-style PHP 7

Using Upstart (e.g. ubuntu):

restart php7.0-fpm         # typical (ubuntu is debian-based) PHP 7
restart php5-fpm           # typical (ubuntu is debian-based)
restart php-fpm            # uncommon

Using systemd (newer servers):

systemctl restart php-fpm.service    # typical
systemctl restart php5-fpm.service   # uncommon
systemctl restart php7.0-fpm.service # uncommon PHP 7

Or whatever the equivalent is on your system.

Nginx + php-fpm – recv() error

Most probably you ran out of php-fpm workers. The log was silent because nothing was wrong in the code itself - workers just were busy processing your requests. If you did not get this on pages without MySQL queries, the bottleneck was the MySQL DB. You should identify long-running queries (using mytop or slow log feature or maybe some custom PHP logging around your SQL processing) and optimize them. Of course, "long queries" are actually quite short in high-load we world. Even 200ms query is long enough to put your server on its knees.

Best Answer

Related Solutions

Nginx – How to restart php-fpm

Nginx + php-fpm – recv() error

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