Hey all, and I hope your AFS journey has been fruitful :)

I've been playing about with tuning the cache manager and fileserver, and
I've gotten things working fairly well. I'm now seeing fairly good write
performance, but its spotty. I am looking at afsmonitor on the client
involved, and I am seeing a large number of vcache misses in afsmonitor
(519000 misses vs 6251 hits, at the moment). My systems are Ubuntu 12.04
and I am using the 1.6.1-1 client and server packages.

Here is some data:

fileserver: /usr/lib/openafs/fileserver -L -sendsize 512000 -b 6000 -p 128
-l 15000 -s 50000 -vc 1000 -cb 8000000 -rxpck 3600 -udpsize 12582912
-busyat 1200 -vattachpar 4
client: /sbin/afsd -stat 1500000 -dcache 9300 -daemons 6 -volumes 256
-chunksize 19 -rxpck 2000 -afsdb -dynroot -fakestat

I'm still learning the ins and outs of tuning, but in following the guide,
I increased the stat parameter to a number something like the number of
files I would be touching in my bulk data operations, volume by volume. The
file size is up to a few megabytes, but averages less than half a megabyte,
so I set the chunksize to half a megabyte. The product of dcache and
chunksize is equal to less than 95% of the cache partition size, which is 5
Gigabytes. I am not dealing with loads of volumes at once in these
operations... two to four at a time.

I am not seeing calls waiting on a thread:

Trying 10.33.10.66 (port 7001):
Free packets: 653/659, packet reclaims: 0, calls: 1583, used FDs: 64
not waiting for packets.
0 calls waiting for a thread
1 threads are idle
4 calls have waited for a thread

The fileserver has only bee "roughly" tuned. I used a set  pf parameters
recommended on the list and increased the callbacks, as well as changed the
udpsize to 90% of the system's allowed size, which was changed using syctl.

My concern is that vcache misses are still high after increasing the -stat
parameter to 1.5 million. The local system has no trouble with this (plenty
of memory and processor to spare) so I could increase things quite a bit
more if needed.

I feel I am missing something.. although I do understand the basics here,
and the relation of the various parameters to activity, I am guessing that
I am missing something important re: tuning client vs. fileserver for bulk
operations. Can anyone advise?

Thanks muchly,

-- 
Timothy Balcer / IT Services
Telmate / San Francisco, CA
Direct / (415) 300-4313
Customer Service / (800) 205-5510

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