Hi all,

I am fairly new to asking questions on a forum so if I need to provide more
details, please let me know.

Worth noting that just as I was about to send this out, I checked and I
don't have the most recent version of HASHPIPE with hashpipe_irqaffinity.sh
among other additions and modifications. So this might fix my problem, but
maybe not and someone else has more insight. I will update everyone if it
does.

I am trying to reduce the number of packets lost/dropped when running
HASHPIPE on a 32 core RHEL 7 server. I have run enough tests and
diagnostics to be confident that the problem is not any HASHPIPE thread
running for too long. Also, the percentage of packets dropped on any given
scan is between about 0.3 and 0.8%. Approx. 5,000 packets in a 30 second
scan with a total of 1,650,000 packets. So while it's a small percentage,
the number of packets lost is still quite large. I have also done enough
tests with 'top', 'iostat' as well as timing HASHPIPE in between time
windows where there are no packets dropped to diagnose the issue further. I
(as well as my colleagues) have come to the conclusion that the kernel is
allowing processes to interrupt HASHPIPE as it is running.

So I have researched and run tests involving 'niceness' and I am currently
trying to configure smp affinities and irq balancing, but the changes that
I make to the smp_affinity files aren't doing anything. My plan was to have
the interrupts run on the 20 cores that aren't being used by HASHPIPE.
Also, disabling 'irqbalance' didn't do anything either. I also restarted
the machine to see whether the changes made are permanent, but the system
reverts back to what it was.

I might be missing something, or trying the wrong things. Has anyone
experienced this? And could you point me in the right direction if you have
any insight?

If you need anymore details, please let me know. I didn't add as much as I
could because I wanted this to be a reasonably sized message.

Thanks,

Mark Ruzindana

-- 
You received this message because you are subscribed to the Google Groups 
"casper@lists.berkeley.edu" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to casper+unsubscr...@lists.berkeley.edu.
To view this discussion on the web visit 
https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/CA%2B41hpxcwSQT-EsjuyqXpGmmBzykDeLt6JbfUUg_ZYpkXyat2w%40mail.gmail.com.

Reply via email to