Date: Sat, 4 Sep 1999 09:40:18 +0930 From: Greg Lehey <grog@lemis.com> To: Gerd Knops <gerti@bitart.com> Cc: questions@FreeBSD.ORG Subject: Re: Vinum: Best performance from mirror setup with two disks Message-ID: <19990904094018.A95378@freebie.lemis.com> In-Reply-To: <19990903235501.9687.qmail@camelot.bitart.com>; from Gerd Knops on Fri, Sep 03, 1999 at 06:55:00PM -0500 References: <19990903232137.9612.qmail@camelot.bitart.com> <19990904090824.Y95378@freebie.lemis.com> <19990903235501.9687.qmail@camelot.bitart.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Friday, 3 September 1999 at 18:55:00 -0500, Gerd Knops wrote: > Greg Lehey wrote: >> On Friday, 3 September 1999 at 18:21:36 -0500, Gerd Knops wrote: >>> Hi, >>> >>> I have read everything I could find about vinum (man pages, recent >>> questions Mailing list, Vinum intro) but I am still not quite sure: >>> >>> What is the best performing setup to get mirroring with two disks? >>> >>> I understand that I just set up one plex per disk. Write performance goes >>> down due to double writes, read performance goes up since vinum will >>> alternate reads between the plexis. >> >> Correct. >> >>> What I don't quite understand is if striping gives me an added advantage >>> in this scenario. >> >> It depends a lot on your usage. In general, a striped plex will give >> more even access to the two drives, so the performance is likely to be >> better. >> > I still don't get that. In the case of a two disk mirror, how can striping > help performance if reads are already alternated between the two plexes > (which are on different disks)? I didn't say it would help read performance, but it'll help write performance. Don't expect to see a big improvement, though. Greg -- When replying to this message, please copy the original recipients. For more information, see http://www.lemis.com/questions.html See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19990904094018.A95378>