On Thu, May 20, 2010 at 8:34 PM, Richard Elling <richard.ell...@gmail.com> wrote: > On May 20, 2010, at 11:07 AM, Asif Iqbal wrote: > >> On Thu, May 20, 2010 at 1:51 PM, Asif Iqbal <vad...@gmail.com> wrote: >>> I have a T2000 with a dual port 4gb hba (QLE2462) and a 3510FC with >>> one controller 2gb/s attached to it. >>> I am running sol 10 u3 . >>> >>> every time I change the recordsize of the zfs fs the disk IO improves >>> (doubles) and stay like that for >>> about 5 to 6 hrs. Then it dies down. I increase the recordsize again >>> and performace jumps back to >>> double again. The main app is oracle database with 8K blocksize >>> >>> I changed the zfs recordsize to from 8K to 16K and then 32K every 8 >>> hrs, which improved the disk IO >>> >>> I wonder if there is any other zfs parameter that I can change to keep >>> the performance good, since I >>> am running older sol 10. >>> >>> I have single disk luns on the 3510 with mpxio enabled on T2000. each >>> disk has two paths (primary,primary) >>> online per luxadm. >>> >>> zpool iostat 10 gives me only about 6MB max write bandwidth. I was >>> hoping it to lot higher. >>> >>> the battery on 3510 is expired and waiting for a replacement. >>> >>> besides replacing the battery, what else can I do to improve the write >>> bandwidth? >>> >>> does the battery expire directly affecting the oracle's disk IO? I >>> thought oracle will just write to zfs and done. >>> and zpool will then write-through to controller instead of write-back >>> since no battery. >>> >>> sun storage guys found no other issue besides the battery. >>> >>> should disabling zil improve performance? I won't try it until we get >>> the battery so not to risk data loss >>> during outage. >> >> so my 3510 is essentially behaving like a 3510 jbod but why would that >> make the IO bandwidth this low? > > The application is not driving enough load to make the bandwidth be
know of an one liner how to test the high write bandwidth can reach ? I know sequential read bandwidth (dd) and random read bandwidth (find) test. But do not know of one for write. > higher. Why? Because it is an Oracle database and will be making > sync writes, by default. Since you do not have a working battery, those would be nice if there is a way to tell oracle to let zpool do the sync write instead > writes are taking 10-40ms each. Replace your battery. i was told by app team that, another similar setup (t2000+4port hba+3510+6 LD raidz2) performed twice as high disk write IO and i checked the battery is expired on that one too unfortunately we failed over to this server to do maintenance on that setup. so no way to verify that observation.. heh. oh well > -- richard -- Asif Iqbal PGP Key: 0xE62693C5 KeyServer: pgp.mit.edu A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
