lkml.org 
[lkml]   [2006]   [Oct]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: to many sockets ?
Alan Cox schrieb:
> Ar Mer, 2006-10-04 am 17:03 +0200, ysgrifennodd Markus Wenke:
>
>> Hi,
>>
>> I wrote a program which handles incomming sockets asynchron.
>> It can handle up to 140000 connections simultaneously while every
>> connection send some bytes in both directions continuously.
>>
>
> Armwavingly 64K x 2 per socket worst case for non tcp windowed buffering
>
> 128K per socket x 140000 connections
>
> 8750MB of RAM
>
> plus other overhead
>
> Assuming you kept the socket buffer limit to 64K by setting it or
> disabling window scaling you'd want a about 10GB of RAM for the sockets,
> buffering and resources. With tcp windows you'd need more.
The default values of my system are:
SO_SNDBUF = 16384
SO_RCVBUF = 87380

> If your data rates are always low, or the link is low latency you could
> set the send/receive socket buffer for each connection via setsockopt
> down to say 8K and come out needing perhaps 1GB or so instead.
>
I tried the same scenario with SO_SNDBUF = SO_RCVBUF = 8k, so that the
max memory is ca. 2G
and the oom-killer kills my application at the same time (at 140000
connections).

I can not see in the messages that the system is out of memory,
there is also no swap space used

You can download my /var/log/messages at
http://hemaho.mine.nu/~biber/messages

May you can give me a hint which line/value in the log shows me,
that the system is out of memory?


Thanks in advance

Markus Wenke

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2006-10-05 09:17    [W:0.105 / U:0.096 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site