Subject: Re: 32 core net-next stack/netfilter "scaling"

From: Rick Jones <[email-masked]>
Date: Tue, 27 Jan 2009 14:43:20 -0800

> 
> By any chance, are you using SLAB instead of SLUB ?

Seems that way:

sut42:~/net-next-2.6# grep SLAB .config
CONFIG_SLAB=y
CONFIG_SLABINFO=y
# CONFIG_DEBUG_SLAB is not set
sut42:~/net-next-2.6# grep SLUB .config
# CONFIG_SLUB is not set

The config file should be up under the base URL:

ftp://ftp.netperf.org/iptable_scaling

The system started as a Debian Lenny with a 2.6.26 kernel, and I did a make old 
config and mostly took defaults (save multiq)

> While running your netperf session, issuing :
> 
> grep conntrack /proc/slabinfo
> 
> Would help to know hash dispertion on your machine.

sut42:~/net-next-2.6# grep conntrack /proc/slabinfo
nf_conntrack_expect      0      0    240   66    1 : tunables  120   60    8 : 
slabdata      0      0      0
nf_conntrack         276    742    304   53    1 : tunables   54   27    8 : 
slabdata     14     14      0

about a minute later it is:

grep conntrack /proc/slabinfo
nf_conntrack_expect      0      0    240   66    1 : tunables  120   60    8 : 
slabdata      0      0      0
nf_conntrack         315    742    304   53    1 : tunables   54   27    8 : 
slabdata     14     14      0

after about another 40 to 60 seconds it was:

grep conntrack /proc/slabinfo
nf_conntrack_expect      0      0    240   66    1 : tunables  120   60    8 : 
slabdata      0      0      0
nf_conntrack         314    742    304   53    1 : tunables   54   27    8 : 
slabdata     14     14      7