Re: to many sockets ?

From: Markus Wenke
Date: Thu Oct 05 2006 - 05:16:38 EST


Eric Dumazet schrieb:
On Thursday 05 October 2006 10:20, Markus Wenke wrote:
Eric Dumazet schrieb:

Could you post here the result of these commands when your system is
using more than 100.000 connections (and before the OOM :) )
Hi,

here the results with 130001 connetions

cat /proc/meminfo
MemTotal: 3108372 kB
MemFree: 2114404 kB
Buffers: 5112 kB
Cached: 97804 kB
SwapCached: 0 kB
Active: 140552 kB
Inactive: 38948 kB
HighTotal: 2228160 kB
HighFree: 2048108 kB
LowTotal: 880212 kB
LowFree: 66296 kB

See here ? you have 'only' 880212 kB of LOWMEM, and 66 MB free.
all kernel structures (you can see them in /proc/slabinfo) are lying on this zone, no matter you add RAM on your machine (more RAM end up in HighMEM zone, wich is basically unused on your setup)

Since you have a 64bits CPU, your best move would be to use a 64bits kernel (you can keep all user land in 32bits mode)

With a 64bits kernel, kernel land structures would not be constrained in a small area, but can use full RAM.

I think I change to the 64 Bit-Kernel ;-).


btw: with the Xen-patched Kernel I get this at 130000 connections:

MemTotal: 2979840 kB
MemFree: 2394544 kB
Buffers: 5748 kB
Cached: 104492 kB
SwapCached: 0 kB
Active: 146632 kB
Inactive: 43276 kB
HighTotal: 2136004 kB
HighFree: 1943728 kB
LowTotal: 843836 kB
LowFree: 450816 kB
SwapTotal: 2104472 kB
SwapFree: 2104472 kB
Dirty: 412 kB
Writeback: 0 kB
Mapped: 89556 kB
Slab: 285284 kB
CommitLimit: 3594392 kB
Committed_AS: 205244 kB
PageTables: 756 kB
VmallocTotal: 114680 kB
VmallocUsed: 4576 kB
VmallocChunk: 109280 kB

I'm curious you have so many sockets but few entries in route cache... basically all connections come from few machines ?

My test scenario has only 5 clients, so I must make the connections with a few clients.



Thanks a lot

Markus Wenke

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