4

I have installed ngix + php5-fpm. I am happy with it but I can not optimize php5-fpm so that it works without errors. Each fixed error creates a different error.

First I had the the default settings which causet a lot of errors:

[04-Jun-2012 03:30:06] WARNING: [pool www] server reached pm.max_children setting (5), consider raising it

I increased all numbers:

pm.max_children = 15 pm.start_servers = 5 pm.min_spare_servers = 3 pm.max_spare_servers = 5 ;pm.max_requests = 500

It caused a different error:

[28-Feb-2013 07:45:06] WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 8 children, there are 18 idle, and 28 total children

I increased all numbers again:

pm.max_children = 70 pm.start_servers = 20 pm.min_spare_servers = 20 pm.max_spare_servers = 35 ;pm.max_requests = 500

This caused logfile filling up with this:

[28-Feb-2013 13:21:55] NOTICE: [pool www] child 21868 exited with code 0 after 4171.293476 seconds from start [28-Feb-2013 13:21:55] NOTICE: [pool www] child 23962 started

I uncommented:

pm.max_requests = 500

I had the same errors, but not so often - every 5 minutes:

[28-Feb-2013 13:21:55] NOTICE: [pool www] child 21868 exited with code 0 after 4171.293476 seconds from start [28-Feb-2013 13:21:55] NOTICE: [pool www] child 23962 started

I did increase again:

pm.max_requests = 1000

Now I have this error 2-3 times per hour but it still persists.

I would increase this number again but I feel that my server (websites) work a bit slower than websites hosted on another server with settings: pm.max_children = 15,pm.start_servers = 5, pm.min_spare_servers = 3, pm.max_spare_servers = 5. (probably it's just a network issue, I don't know).

I have searched Google and this website and know how to calculate the pm.max_children (it depends of RAM). But I can not find any information how to calculate:

 pm.start_servers pm.min_spare_servers pm.max_spare_servers pm.max_requests

Can somebody help?

uptime 13:55:39 up 16:40, 2 users, load average: 0.13, 0.14, 0.16 free -m total used free shared buffers cached Mem: 24101 3783 20318 0 151 3039 -/+ buffers/cache: 592 23509 Swap: 7811 0 7811

I did not change anything in nginx configuration files.

Improve this question
5
  • It sounds like you have done all the correct steps to tune PHP-FPM. What problem are you having? Commented Feb 28, 2013 at 23:18
  • The problem is the following lines in php5-fpm.log. Is it normal? [28-Feb-2013 13:21:55] NOTICE: [pool www] child 21868 exited with code 0 after 4171.293476 seconds from start [28-Feb-2013 13:21:55] NOTICE: [pool www] child 23962 started Commented Mar 1, 2013 at 5:39
  • That's normal since you set pm.max_requests. Commented Mar 1, 2013 at 5:41
  • ok, but what is the purpose of pm.max_requests? By default is not activated. Commented Mar 2, 2013 at 9:44
  • 2
    As far as I know, it will kill the child and so force the creation of a new child. This will reduce the damage done by memory leaks, as all memory of the child is freed when killed. Commented Apr 3, 2013 at 19:57

2 Answers 2

Reset to default
2

As it says in the log [NOTICE]: this is informational and not an error. These are marked [ERROR].

So in short: nothing to worry about. It's like your kid telling you they switched off the light in the kitchen.

If it says [WARNING] that's something you should take care of, like you did in your first response by increasing the thresholds.

Improve this answer
0

Switch php-fpm to dynamic mode. That way php-fpm automatically decides when to spawn new children. It is must have if you're using and type of opcode caches, because force-killed children increase fragmentation in PHP-APC

Improve this answer
0

You must log in to answer this question.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.