Mickae?l ABISROR
2008-Jun-19 08:10 UTC
[zfs-discuss] Questions from a top cust interested in ZFS
> Hi all, > > here are some questions about ZFS asked by a top customer > > > When accessing to RAW volumes under ZFS do we go through cache or not? > If yes can we disable it? > They use Veritas QuickIO (ODM) and they want to compare with ZFS and > also ZFS with and without cache. > > Do we have some benchmark or figures about the compression CPU > overhead with ZFS? and for Checksumming? > > I''ve seen 1ghz/500mbytes of data for checksumming but it seems to me > that''s huge...What about also the update of ZFS? Do we update with packages, patches, kernel patches or Solaris release?> > Cheers > > Mike
>> Hi all, >> >> here are some questions about ZFS >> >> When accessing to RAW volumes under ZFS do we go through cache or >> not? If yes can we disable it? >> They use Veritas QuickIO (ODM) and they want to compare with ZFS and >> also ZFS with and without cache. >> >> Do we have some benchmark or figures about the compression CPU >> overhead with ZFS? and for Checksumming? >> >> I''ve seen 1ghz/500mbytes of data for checksumming but it seems to me >> that''s huge... > > What about also the update of ZFS? Do we update with packages, > patches, kernel patches or Solaris release? > >> >> Cheers >> >> Mike >
Mickae?l ABISROR wrote:>>> Hi all, >>> >>> here are some questions about ZFS >>> >>> When accessing to RAW volumes under ZFS do we go through cache or >>> not? If yes can we disable it? >>>I believe Zvols are uncached.>>> They use Veritas QuickIO (ODM) and they want to compare with ZFS and >>> also ZFS with and without cache. >>>Please see the discussions on "directio" at http://www.solarisinternals.com//wiki/index.php?title=Category:ZFS http://blogs.sun.com/bobs/entry/one_i_o_two_i http://blogs.sun.com/bobs/entry/oracle_i_o_supply_and http://www.solarisinternals.com/wiki/index.php/Direct_I/O>>> Do we have some benchmark or figures about the compression CPU >>> overhead with ZFS? and for Checksumming? >>> >>> I''ve seen 1ghz/500mbytes of data for checksumming but it seems to me >>> that''s huge... >>>I believe you mean 1 GHz/500 MBytes/s which is reasonable. That is a rather substantial bandwidth for database.>> What about also the update of ZFS? Do we update with packages, >> patches, kernel patches or Solaris release? >>Yes. The exact mix depends on your OS and release. -- richard