sw-engine Plesk Onyx导致内存不足错误

Question

I'm trying to run a large php-scipt that starts every hour if the one before is already finished.

Now I'm getting Out of Memory errors and if I analyze "top" the sw-engine task is consuming a lot of memory and this memory isn't freed anytime. Installed Plesk Onyx Version 17.8.11 Update #17 - using php 7.2.9.

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
  4626 psaadm   20  0    8838088 8.195g 17344 S  1.7  34.1    9:23.35 sw-engine

Any idea on how to get rid of the sw-engine consuming all the ressources?

Why is sw-engine consuming ressources when I simply start a scheduled task?

Answer 1

sw-engine is a PHP-FPM handler, which is used by Plesk internally, to run, for example, Plesk UI and PHP scripts as scheduled tasks:

# sw-engine -v
PHP 7.1.14 (cli) (built: Apr  9 2018 16:55:38) ( NTS )
Copyright (c) 1997-2018 The PHP Group
Zend Engine v3.1.0, Copyright (c) 1998-2018 Zend Technologies

Instead of sw-engine, you can use any PHP version installed on the server. For example, /usr/bin/php for PHP provided by OS vendor, or /opt/plesk/php/7.2/bin/php for PHP 7.2 shipped with Plesk.

To do that, simply create a scheduled task with Run a command type, and prepend the path to the script with the path to PHP executable:

As per OOM issue, sw-engine uses 256 MB memory limit by default:

# grep limit /usr/local/psa/admin/conf/php.ini
memory_limit = 256M

So it looks like the memory limit is redefined somewhere in the script itself. You can verify if as follows:

# grep -i memory_limit /path/to/script.php

Also, you can try to run it manually to see how it performs with different PHP versions to see if there is any difference:

# /usr/bin/php /path/to/script.php
# /usr/sbin/php-fpm /path/to/script.php
# /usr/sbin/sw-engine-fpm /path/to/script.php
# /opt/plesk/php/7.2/bin/php /path/to/script.php