Date: Thu, 19 Jun 2003 09:57:35 +0300 From: "Petri Helenius" <pete@he.iki.fi> To: "Jin Guojun [DSD]" <j_guojun@lbl.gov> Cc: Scott Long <scottl@freebsd.org> Subject: Re: freebsd-performance Digest, Vol 4, Issue 7 Message-ID: <042501c33630$115159a0$812a40c1@PETEX31> References: <20030614190033.7F0DE37B407@hub.freebsd.org><20030615091254.M85497@bluhayz.org> <3EF0B507.2B1B6FDF@lbl.gov> <002101c335d9$f6664a20$812a40c1@PETEX31> <3EF0EABC.E9D75759@lbl.gov>
next in thread | previous in thread | raw e-mail | index | archive | help
> But this seems to have different problem. At least write to RAID 1 requires > twice bus bandwidth for soft RAID 1. So, read should be faster than write. > But current read is 67 MB/s, write is 10 MB/s. Something is not working. Might be that whatever youīre using for the write waits for the second write to complete before it issues a write on the first drive again. vinum does this, it does not dispatch both writes at the same time. (I argued about this being "broken" for a while but then gave up, I understand why doing this differently does complicate the code, but at the same time improves performance) > > Yes, but adaptec guy says that go find one if you could because 5400 is good. > They told that 2xxxS has lower performance than 5400. > This would require faith in the fact that the aac driver will get fixed. It should be noted that I have not tested it with 5400 but tests with 2120S have random failures (shutdowns never complete, containerconfig gets read only sporadically, some operations hang for a relatively long time, etc.) so although I would like to use something like the above mentioned cards, it would jump in a dark, even compared with usually downplayed ATA RAID based solutions. > > And currently there are also the reliability issues with drivers like aac > > (Adaptec 2120S and 2200S, etc.) "no frills" SCSI or ATA controllers > > run much more reliably and have more user base so the issues get ironed > > out quicker. > > They are fixing the driver now, hopefully we will get newer one next week. > Scottl fixed a bug related to the aaccli interface about two weeks ago, havenīt heard from him since. Itīs good news that the driver is getting actively worked on. (although I keep hearing that his is not exactly getting paid on fixing it) Pete
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?042501c33630$115159a0$812a40c1>