On Mon, 11 Aug 2008 02:09:17 PDT Martin Svensson <[EMAIL PROTECTED]> wrote:
> I read this (http://blogs.sun.com/roch/entry/when_to_and_not_to) blog > regarding when and when not to use raidz. There is an example of a plain > striped configuration and a mirror configuration. (See below) > > M refers to a 2-way mirror and S to a simple dynamic stripe. > > Config Blocks Available Random FS Blocks /sec > ------------ ---------------- --------- > M 2 x (50) 5000 GB 20000 > S 1 x (100) 10000 GB 20000 > > Granted, the simple striped configuration is fast, and of course with no > redundancy. But I don't understand how a mirrored configuration can perform > as good when you sacrifice half of your disks for redundancy. Doesn't a > mirror perform as one device? Can someone please clarify the example from the > above, I think I am missing something? Generally, switching to mirror means you lose write performance, as you have to write the blocks twice. On the other hand, you gain read performance, because you can now schedule reads from either disk. <mike -- Mike Meyer <[EMAIL PROTECTED]> http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. O< ascii ribbon campaign - stop html mail - www.asciiribbon.org _______________________________________________ opensolaris-help mailing list opensolaris-help@opensolaris.org
