raidtest for zfs

[Michael Monashev]

Здравствуйте, Pawel.

> What's strange about those results? Can you show us 'zpool status' and
> explain what you expect and why?

> zpool status
  pool: tank
 state: ONLINE
 scrub: none requested
config:

        NAME        STATE     READ WRITE CKSUM
        tank        ONLINE       0     0     0
          raidz1    ONLINE       0     0     0
            ad6s1   ONLINE       0     0     0
            ad8s2   ONLINE       0     0     0
            ad10s3  ONLINE       0     0     0
            ad12s1  ONLINE       0     0     0
            ad14s2  ONLINE       0     0     0

errors: No known data errors

I  compare  graid5,  graid3+gcache,  raidz. My target is find software
RAID  with  better  read  performance and huge storage size. I planing
place a lot of little (1-100kb) images on it.

Here is my test results: http://michael.mindmix.ru/168-958-rezul-taty-testirovanija-graid5-graid3-gcache-i-raidz.zhtml

graid3+gcache with round-robin reading is 1.25 faster than 1 disk.
graid5 is 2.18 faster than 1 disk.
raidz is 7.7 faster than 1 disk.

5 disks cant read faster than 5 times. raidz is 7.7 faster than 1
disk!

This is strange for me.

>> [...] How to turn off zfs cache completely?

> You can't, but for reading you just need to export/import your pool to
> get rid of existing cache.




-- 
С уважением,
 Michael                          mailto:softsearch at gmail.com