Op 08-10-15 om 13:21 schreef Graeme B. Bell:
First the database was on a partition where compression was enabled, I changed it to an uncompressed one to see if it makes a difference thinking maybe the cpu couldn't handle the load.
It made little difference in my case.
My regular gmirror partition seems faster:
dd bs=8k count=25600 if=/dev/zero of=./test
25600+0 records in
25600+0 records out
209715200 bytes transferred in 1.513112 secs (138598612 bytes/sec)
the zfs compressed partition also goes faster:
dd bs=8k count=25600 if=/dev/zero of=./test
25600+0 records in
25600+0 records out
209715200 bytes transferred in 0.979065 secs (214199479 bytes/sec)
but this one didn't really go that fast in my test (maybe 10%)
Please can you run iozone and look for low random write performance with small blocks? (4k)
http://www.slashroot.in/linux-file-system-read-write-performance-test
Like this ?
gmirror (iozone -s 4 -a /dev/mirror/gm0s1e) = 806376 (faster drives)
zfs uncompressed (iozone -s 4 -a /datapool/data) = 650136
zfs compressed (iozone -s 4 -a /datapool/data) = 676345
Also please can you CC to the list with your replies to my on-list emails?
Graeme Bell
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