Thread (42 messages) 42 messages, 5 authors, 2009-02-20

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

From: Rick Jones <hidden>
Date: 2009-01-27 19:24:59
Also in: netfilter-devel

quoted
I will give it a try and let folks know the results - unless told 
otherwise, I will ass-u-me I only need rerun the "full_iptables" test 
case.

The runemomniagg2.sh script is still running, but the initial cycles 
profile suggests that the main change is converting the write_lock time 
into spinlock contention time with 78.39% of the cycles spent in 
ia64_spinlock_contention. When the script completes I'll upload the 
profiles and the netperf results to the same base URL as in the basenote 
under "contrack01/"
The script completed - although at some point I hit an fd limit - I think I have 
an fd leak in netperf somewhere :( .

Anyhow, there are still some netperfs that end-up kicking the bucket during the 
run - I suspect starvation because where in the other configs (no iptables, and 
empty iptables) each netperf seems to consume about 50% of a CPU - stands to 
reason - 64 netperfs, 32 cores - in the "full" case I see many netperfs consuming 
100% of a CPU.  My gut is thinking that one or more netperf contexts gets stuck 
doing something on behalf of others.  There is also ksoftirqd time for a few of 
those processes.

Anyhow, the spread on trans/s/netperf is now 600 to 500 or 6000, which does 
represent an improvement.

rick jones

PS - just to be certain that running-out of fd's didn't skew the results I'm 
rerunning the script with ulimit -n 10240 and will see if that changes the 
results any.  And I suppose I need to go fd leak hunting in netperf omni code :(
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help