php-fpm runs into futex_wait.

futex(0x2b01a4d57088, FUTEX_WAIT, 2, NULL) = -1 EAGAIN (Resource temporarily unavailable)
futex(0x2b01a4d57088, FUTEX_WAKE, 1) = 0

What is php-fpm trying to lock to..?

Sometimes it goes into FUTEX_WAIT and never recovers


27321 19:54:17.275637 futex(0x2b7adf7dd088, FUTEX_WAIT, 2, NULL <unfinished ...>
27433 19:54:19.427321 open("/etc/group", O_RDONLY <unfinished ...>
27452 19:54:20.527321 <... stat resumed> {st_mode=S_IFREG|0644, st_size=5552, ...}) = 0
27488 19:54:21.327321 close(357 <unfinished ...>
27321 19:54:21.384084 <... futex resumed> ) = -1 EINTR (Interrupted system call)
27321 19:54:21.384876 --- SIGTERM (Terminated) @ 0 (0) ---
27512 19:54:21.627321 close(76 <unfinished ...>


All the child processes are going into futex_wait and are ultimately getting killed after execution_timeout
The new child processes created also follow the same... and ultimately we have to restart php-fpm or wait
for php-fpm to recover after a random time(some mins/hours)

Hi, jabutee!

We have the same problem!
Over time after php5-fpm started on test-server with moderate load (not heavy load) all child processes (static pool) are going into futex_wait. And new child processes has the same state.

Did you solve this issue?

We have the exactly same problem on test server :( And do not know how to fix it...

https://www.google.nl/#q=nginx+FUTEX_WAIT+EAGAIN
https://groups.google.com/forum/#!topic/mechanical-sympathy/QbmpZxp6C64
https://support.datastax.com/hc/en-us/articles/206259833-Nodes-appear-unresponsive-due-to-a-Linux-futex-wait-kernel-bug

---
nginx for Windows http://nginx-win.ecsds.eu/

Hi, itpp2012!

Thx, for you answer!
Unfortunately, issue is still exists!

We have kernel

uname -r
3.13.0-77-generic

which patched already according your hint

apt-get changelog linux-image-`uname -r` | grep futex
...
* futex: Ensure get_futex_key_refs() always implies a barrier
...

Maybe you have any other suggestions?

Try the latest nginx from hg repo?

---
nginx for Windows http://nginx-win.ecsds.eu/