[OpenAFS-devel] Default params for afsd?

[Harald Barth]

Hi folks,
I am testing cache parameters - trying to tune OpenAFS 1.3.84. Just
now I have

-dcache 100000 -stat 150000 -daemons 27 -volumes 250  -afsdb -files 2000000

in 20000000KB (~20GB) cache. Took half an eternity (~8h) to build.
This is on two old striped SCSI discs, stripesize is 64K. Now I'm
reading a file from the partition without involving AFS:

bash-2.05# time dd if=testfile of=/dev/null bs=`expr 1024 \* 64`
3654+1 records in
3654+1 records out

real    0m26.055s
user    0m0.000s
sys     0m3.760s

=> 9210660 bytes/sec, say 10MB/sec

And now the same file from AFS from the same (hot) partition used as cache

bash-2.05# time dd if=afsfile of=/dev/null bs=`expr 1024 \* 64`
3654+1 records in
3654+1 records out

real    0m38.598s
user    0m0.010s
sys     0m11.700s

=> 6302030 bytes/sec, say 6.3MB/sec

I'm reading the same data with the same blocksize (happens to be
=stripesize so be extra nice) from the same discs. And raw is 50% than
AFS?

Then of course I'm open for tunig tips, chunksize=20 is next I think. Should
I go for concatenating instead of striping? 
bash-2.05# uname -a
SunOS ketchup.stacken.kth.se 5.9 Generic_118559-05 i86pc i386 i86pc

bash-2.05# metastat d3
d3: Concat/Stripe
    Size: 57227240 blocks (27 GB)
    Stripe 0: (interlace: 128 blocks)
        Device     Start Block  Dbase   Reloc
        c1t0d0s3          0     No      Yes
        c1t1d0s3          0     No      Yes

Device Relocation Information:
Device   Reloc  Device ID
c1t0d0   Yes    id1,sd@SCOMPAQ__MAA3182SC_______53056172____9906
c1t1d0   Yes    id1,sd@SCOMPAQ__MAA3182SC_______53051962____9903

Final goal is to build an ftp server that can serve with 10MBytes/sec
from a big cache on HW that was for free.

Harald.

PS, Murphy SCSI style: Either HD is SCA and cable is 68-pin or HD is
    68-pin and bay is SCA.