2001-02-12 20:32:10

by Alexey Kuznetsov

[permalink] [raw]
Subject: Re: 2.4.1 errors under heavy network load

Hello!

> Then we did the following tuning attempt:

Please, cat /proc/net/tcp and /proc/net/sockstat
and send result to me (gzipped), together with /proc/sys/net/ipv4/tcp_*
values


> echo "20480" > /proc/sys/net/ipv4/tcp_max_orphans

Also, you want to increase memory allowed for TCP
echo "X/2 X/2 X" > /proc/sys/net/ipv4/tcp_mem
where X is memory in pages.

20480 is a crazy number. Valid applications cannot leave
so much of orphans. Do you understand that this is more than
80MB of wasted memory?


> echo "1" > tcp_orphan_retries

Bad idea. Default value is the lowest possible.


> echo 30 > /proc/sys/net/ipv4/tcp_keepalive_time
> echo 2 > /proc/sys/net/ipv4/tcp_keepalive_probes

Bad idea.



> Oh btw. we got what I think is a "bad one" too...
> Feb 12 16:42:35 mcquack kernel: KERNEL: assertion (tp->lost_out == 0) failed
> at tcp_input.c(1202):tcp_remove_reno_sacks

Absolutely harmless. This is debugging message.

Alexey