Guys,
Have an opensolairs x86 box running:
SunOS thsudfile01 5.11 snv_111b i86pc i386 i86pc Solaris
This has 2 old qla2200 1Gbit FC cards attached. Each bus is connected to an old
transtec F/C raid array. This has a couple of large luns that form a single
large zpool:
r...@thsudfile01:~# zpool status bucket
pool: bucket
state: ONLINE
scrub: none requested
config:
NAME STATE READ WRITE CKSUM
bucket ONLINE 0 0 0
c5t0d0 ONLINE 0 0 0
c8t3d0 ONLINE 0 0 0
errors: No known data errors
r...@thsudfile01:~# zfs list bucket
NAME USED AVAIL REFER MOUNTPOINT
bucket 2.69T 5.31T 22K /bucket
This is being used as an iSCSI target for an ESX 4.0 development environemnt. I
found the performance to be really poor and found the culprit seems to be write
performance to the raw zvol. For example on this zfs filesystem allocated as a
volume:
r...@thsudfile01:~# zfs list bucket/iSCSI/lun1
NAME USED AVAIL REFER MOUNTPOINT
bucket/iSCSI/lun1 250G 5.55T 3.64G -
r...@thsudfile01:~# dd if=/dev/zero of=/dev/zvol/rdsk/bucket/iSCSI/lun1
bs=65536 count=102400
^C7729+0 records in
7729+0 records out
506527744 bytes (507 MB) copied, 241.707 s, 2.1 MB/
Some zpool iostat 1 1000:
bucket 2.44T 5.68T 0 203 0 2.73M
bucket 2.44T 5.68T 0 216 0 2.83M
bucket 2.44T 5.68T 0 120 63.4K 1.58M
bucket 2.44T 5.68T 2 350 190K 16.9M
bucket 2.44T 5.68T 0 123 0 1.64M
bucket 2.44T 5.68T 0 230 0 3.02M
Read performance from that zvol (assuming /dev/null behaves properly) is fine:
r...@thsudfile01:/bucket/transtec# dd of=/dev/null
if=/dev/zvol/rdsk/bucket/iSCSI/lun1 bs=65536 count=204800
204800+0 records in
204800+0 records out
13421772800 bytes (13 GB) copied, 47.0256 s, 285 MB/s
Somewhat optimistic that... but iostat shows 100MB/s ish.
Write to a zfs filesystem from that zpool is also fine, here with a a write big
enough to exhaust the machines 12GB memory:
r...@thsudfile01:/bucket/transtec# dd if=/dev/zero of=FILE bs=65536 count=409600
^C
336645+0 records in
336645+0 records out
22062366720 bytes (22 GB) copied, 176.369 s, 125 MB/s
and bursts of cache flush from iostat:
bucket 2.44T 5.68T 0 342 0 38.7M
bucket 2.44T 5.68T 0 1.47K 0 188M
bucket 2.44T 5.68T 0 240 0 21.3M
bucket 2.44T 5.68T 0 1.54K 0 191M
bucket 2.44T 5.68T 0 1.49K 0 191M
bucket 2.44T 5.68T 0 434 0 44.2M
So we seem to be able to get data down to disk via the cache at a reasonable
rate and read from a raw zvol OK, but writes are horribly slow.
Am I missing something obvious? let me know what info would be diagnostic and
I'll post it...
Cheers,
Leon
--
This message posted from opensolaris.org
_______________________________________________
zfs-discuss mailing list
zfs-discuss@opensolaris.org
http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
