[OpenAFS] Performance problems seem to be coming back
Fri, 09 Sep 2011 09:41:10 -0400
Earlier this year I posted about AFS performance problems on our
network, which were related to underlying network performance problems.
Remedial actions were taken and longer-term strategies put in place, and
things got better.
At least for a while. Over the past few weeks, it seems that
occasionally things are getting bad again, though nowhere nearly as bad
as they were earlier this year. I guess I should say here that I don't
have access to the servers, in order to do any sort of metrics there.
I'm gearing up for the battle with the support people, to convince them
that there is a problem, and I'm not just a "picky user." That job is
complicated by the fact that we have many complacent, accepting users
around here, so this often turns into a matter of, "It's only you guys
Part of the problem has been metrics. We (or at least I) don't really
seem to have to tools and techniques to see what's going on here.
During the previous problem timeframe, "smokeping" turned out to be a
critical diagnostic tool, crude as it was. At that time I got the
impression that what I'd really like to be doing is monitoring the round
trip time for afs communications. I took a brief look at wireshark,
played with filtering, and managed to watch the afs packets go and
return, and am pretty sure that there was enough information there to do
such monitoring. I also got the impression that wireshark supported
some sort of "filter macros" to make this process automatic, and that
some stuff was available for afs. I started looking into it, but it
looks to me as if all of this stuff was meant for someone more expert
than I, so I didn't get far. Plus about that time our network started
getting better, and because of the network problems we were behind on
our "real work", etc. It got dropped.
Does anyone have advice on how to, as simply and automatically as
possible, monitor and log afs packet round trip times?
Phone: (802) 769-6850
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