Hi XFS gurus,
Firstly you're all doing a great job and I am way impressed by the
solidity, and both speed of porting, and speed of the filesystem...
However, (and I guess you knew this was coming :-) I tried writing to
an XFS partition over NFS again - this time using work machines
instead of home, and the performance was a still a bit of a worry
to say the least.
The results are below. Is there anything more that I can do to try
and diagnose the problem for y'all? Or anything that I can use to
boost NFS performance? I heard someone talk about a userland nfsd -
might that help, and where would I find it?
machine/config this time:
dual celeron 500, ASUS bp6, 512M ram, 4x maxtor 60G/7200rpm drives,
2x promise ultra100 controller cards (each drive on its own controller),
RH7.1beta, 2.4.2-XFSsmp-3mar2001 kernel. The network is 100Mbit
ethernet (3c905 I think). Reiserfs was not timed as it was unable to
make >2G files(!!)
time dd if=/dev/zero of=bigFile bs=1024k count=2500
writes to local disk writes over nfs notes
xfs 16 MB/s 0.7 MB/s load ~90-100% per cpu + (*)
xfs over RAID0 37 MB/s 1 MB/s ""
xfs over RAID5 didn't try yet
ext2 17 MB/s 8 MB/s load ~30-40% per cpu
ext2 over RAID0 38 MB/s 8 MB/s ""
ext2 over RAID5 14 MB/s 6 MB/s "" + (**)
(*) I tried just one nfsd process as well as the default 8 and the
bandwidth to disk was the same. I thought maybe the knfsd's were
fighting each other, but that seems not to be the case.
(**) this hung the 2nd time I tried it. sigh
So yeah, the disk lights barely flashed at all with XFS writes over
NFS, and speed was about a factor of 10 less than it should be. Using
an NFSv2 or v3 client didn't matter. Nor did writing from IRIX, Tru64
or Linux. Clearly there's some major struggle going on between knfsd
and xfs :-/ Sad to say, but the speed makes it pretty much unusable.
I didn't try server-side NFSv2 as I need big files.
Please let me know if I can try anything out for you.