Bug #63395 [Opn->Csd]: Spawned processes do not perform

Edit report at https://bugs.php.net/bug.php?id=63395&edit=1 ID: 63395 Updated by: bukka@php.net Reported by: Alex at phpguide dot co dot il Summary: Spawned processes do not perform -Status: Open +Status: Closed Type: Bug Package: FPM related Operating System: Ubuntu 12.04 x64 PHP Version: 5.4.8 -Assigned To: +Assigned To: bukka Block user comment: N Private report: N New Comment: There's no a configuration option pm.max_spawn_rate (introduced in PHP 8.1) that allows customizing the rate and preventing this problem. Please see more details in https://github.com/php/php-src/pull/6753 Previous Comments: ------------------------------------------------------------------------ [2017-11-30 17:19:59] federico dot omoto at gmail dot com This is a really old bug that is affecting PHP versions <= 7.2.0. Can we expect it to be fixed soon? ------------------------------------------------------------------------ [2014-04-15 07:39:42] roger dot qiu at polycademy dot com Yep this is definitely a bug. I experienced the same thing. Basically if you have NGINX with upstream keepalive, and if this number is > than the pm.max_children in FPM, then what happens is that, if there is a X amount of concurrent requests (from for example Apache Bench), in which X is greater than the pm.max_children, this will result in Apache Bench freezing and sometimes never completing certain requests. If the keepalive number is lower than the max_children (not equal), this problem then doesn't exist. ------------------------------------------------------------------------ [2013-02-13 09:50:26] php-bugs at puzzled dot xs4all dot nl This bug seems similar to https://bugs.php.net/bug.php?id=60961 ------------------------------------------------------------------------ [2012-10-30 10:20:30] Alex at phpguide dot co dot il Description: ------------ I'm running nginx 1.2.4 with php5-fpm (5.4.8) issuing ab -n 20000 -c 1000 http://localhost/index.php When pm = dynamic pm.max_children = 3000 pm.start_servers = 100 <- this is important pm.max_spare_servers = 1000 I'm having a lot of errors in nginx talking to php [error] 26125#0: *49177 upstream prematurely closed connection while reading response header from upstream, ... "fastcgi://127.0.0.1:9000" [error] 26125#0: *56030 recv() failed (104: Connection reset by peer) while reading response header from upstream, ... upstream: "fastcgi://127.0.0.1:9000" The fpm log shows a lot of WARNING: [pool www] seems busy (you may need to increase pm.start_servers, or pm.min/max_spare_servers), spawning 32 children, there are 0 idle, and X total children When spawning new children reaches a concrete amount nginx stops issuing such errors. This leads me to believe freshly spawned processes do not execute and respond correctly. Now, when I start with 3000 children straight ahead, all connections work properly. No errors in nginx or fpm. pm = dynamic pm.max_children = 3000 pm.start_servers = 3000 <- Straight ahead pm.max_spare_servers = 3000 Test script: --------------- The php code on the server is relatively simple. apc_inc('count111'); sleep(1); echo 'x'; ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=63395&edit=1