Fedora 19 performs poorly

Note: same message also posted in -ru list

I’m trying to migrate from Fedora 14 (2.6.35.14-97.fc14.x86_64) to
Fedora 19 (3.10.11-200.fc19.x86_64)

worker_processes 40;
events {
worker_connections 8000;
use epoll;
}
http {
proxy_headers_hash_max_size 8096; # default was: 512
proxy_headers_hash_bucket_size 128; # default was: 64
variables_hash_max_size 1024;
variables_hash_bucket_size 128;
default_type application/octet-stream;
sendfile on;
keepalive_timeout 65;
charset utf-8;
resolver 127.0.0.1; # necessary for dynamic upstream
resolution
limit_req_log_level warn;
proxy_intercept_errors on;
server {
listen 80;
location = /service_check_nginx { echo “nginx”; }
}
}

Symptoms:

  • ab -n1000000 -c1000 ‘http://localhost/service_check_nginx’ (parallel
    4x, i.e. 4000 simultaneous connections)
    says that some requests take >3sec and/or fails to complete

  • netstat -s:

    1269313 times the listen queue of a socket overflowed
    1282868 SYNs to LISTEN sockets dropped

grows with speed of 2000/sec, sometimes more

  • CPU load is not spread out evenly between workers:

    PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+
    COMMAND
    27671 nobody 20 0 418.6m 149.2m 1.1m S 51.1 0.1 0:00.77
    nginx: worker process
    27685 nobody 20 0 418.6m 149.2m 1.1m S 39.7 0.1 0:01.76
    nginx: worker process
    27661 nobody 20 0 418.6m 149.2m 1.1m S 22.7 0.1 0:01.63
    nginx: worker process
    27688 nobody 20 0 418.6m 149.2m 1.2m S 22.7 0.1 0:01.90
    nginx: worker process
    27697 nobody 20 0 418.6m 149.2m 1.1m S 17.0 0.1 0:00.95
    nginx: worker process
    27666 nobody 20 0 422.0m 152.3m 1.1m R 7.6 0.1 0:01.50
    nginx: worker process
    27701 nobody 20 0 419.3m 149.7m 1.1m S 1.9 0.1 0:00.01
    nginx: worker process
    27650 nobody 20 0 418.6m 149.9m 1.8m S 0.0 0.1 0:03.52
    nginx: worker process
    27658 nobody 20 0 418.6m 149.2m 1.1m S 0.0 0.1 0:01.30
    nginx: worker process
    27664 nobody 20 0 419.0m 149.5m 1.1m S 0.0 0.1 0:01.86
    nginx: worker process
    27669 nobody 20 0 418.6m 149.2m 1.1m S 0.0 0.1 0:00.35
    nginx: worker process
    27672 nobody 20 0 418.6m 149.2m 1.1m S 0.0 0.1 0:00.23
    nginx: worker process

meanwhile, on F14:

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
30042 nobody 20 0 1224m 955m 17m R 41.2 0.4 523:24.45 nginx:
worker process
30038 nobody 20 0 1224m 955m 17m S 39.4 0.4 522:24.30 nginx:
worker process
30047 nobody 20 0 1224m 955m 17m R 39.4 0.4 520:35.36 nginx:
worker process
30053 nobody 20 0 1224m 955m 17m R 39.4 0.4 520:42.77 nginx:
worker process
30027 nobody 20 0 1224m 955m 17m S 37.6 0.4 520:55.20 nginx:
worker process
30036 nobody 20 0 1224m 955m 18m R 37.6 0.4 525:26.07 nginx:
worker process
30037 nobody 20 0 1224m 955m 17m S 37.6 0.4 523:59.09 nginx:
worker process
30041 nobody 20 0 1224m 955m 17m R 37.6 0.4 529:31.88 nginx:
worker process
30049 nobody 20 0 1224m 954m 17m R 37.6 0.4 519:58.73 nginx:
worker process

By the way, if I set worker_connections 800 (worker_processes 40) and
start up “ab -c1000 …” – then ab fails with an error (on F19 only;
fine on F14).

What should I do next?

Hello!

On Wed, Sep 18, 2013 at 04:47:01PM -0700, Konstantin Svist wrote:

Note: same message also posted in -ru list

Please see detailed response in nginx-ru@ list. It’s actually not
a good idea to cross-post.

Short version for others here: from the information provided it
looks more like a testing problem than a real problem.

[…]


Maxim D.
http://nginx.org/en/donation.html