On 11/23/2010 12:29 AM, Dave Chinner wrote:
16 disk MD raid-5
What is the storage hardware and the MD raid5 configuration?
Tyan motherboard with 5400 chipset
dual Xeon E5420
16 disks on this one:
05:00.0 RAID bus controller: 3ware Inc 9650SE SATA-II RAID PCIe (rev 01)
Subsystem: 3ware Inc 9650SE SATA-II RAID PCIe
Flags: bus master, fast devsel, latency 0, IRQ 16
Memory at ce000000 (64-bit, prefetchable) [size=32M]
Memory at d2600000 (64-bit, non-prefetchable) [size=4K]
I/O ports at 3000 [size=256]
[virtual] Expansion ROM at d26e0000 [disabled] [size=128K]
Capabilities: <access denied>
Kernel driver in use: 3w-9xxx
Kernel modules: 3w-9xxx
mdadm --create /dev/md5 --raid-devices=16 --chunk=1024 --level=5
/dev/mapper/perftestvg-xfslv /perftest/xfs xfs
FYI, relatime, attr2, logbufs=8 and noquota are default values that
you don't need to specify.
ok, that was the /proc/mounts line..
mkfs.xfs -l size=128m -d agcount=16 <device>
mount -o delaylog,nobarrier,inode64,logbufs=8,logbsize=256k <device>
Thanks for the test case - I'll try to reproduce this. One more key
piece of information I need: the output of mkfs.xfs so I can see your
filesystem geometry. if you have the filesystem mounted, then the
output of 'xfs_info<mntpt>' will give the same information.
/# xfs_info /perftest/xfs/
meta-data=/dev/mapper/perftestvg-xfslv isize=256 agcount=16,
= sectsz=512 attr=2
data = bsize=4096 blocks=805306368, imaxpct=5
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0
log =internal bsize=4096 blocks=32768, version=2
= sectsz=512 sunit=0 blks, lazy-count=0
realtime =none extsz=4096 blocks=0, rtextents=0
It is stable enough that all my local machines are running with
delaylog. And as a dev team, we have enough confidence in it to
remove the EXPERIMENTAL status for the 2.6.37 release. That doesn't
mean it is perfectly bug free - it just means more people will start
to use it. And as this happens, we will find new problems in
different environments (just like you have), but this is a pretty
normal occurrence for new code.
ok I understand...
thanks for your work!