Date: Fri, 29 Sep 2006 14:59:41 -0500 From: Albert Chin <freebsd-stable@mlists.thewrittenword.com> To: freebsd-stable@freebsd.org Subject: Re: Poor write performance with LSI 320-2 on 6.1-STABLE Message-ID: <20060929195941.GD53879@mail1.thewrittenword.com> In-Reply-To: <451D4ACA.1040504@samsco.org> References: <20060928221505.GA75187@mail1.thewrittenword.com> <451D4ACA.1040504@samsco.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Sep 29, 2006 at 10:33:14AM -0600, Scott Long wrote: > Albert Chin wrote: > >I have an Intel S875PWP1 motherboard with a Pentium4 CPU@2.40GHz. PCI > >bus is 33Mhz, 32-bit. I recently purchased an LSI 320-2/128MB on eBay > >(though the card really looks like a PERC4/DS) and just ran some > >bonnie++ tests on a RAID 1 array between two U320 drives for the first > >channel and on a RAID 0 array between one U320 drive for the second > >channel. The 320-2 has the latest LSI firmware, 1L47. > > > [...] > > > >I don't understand how #1 gives 16MB/s (RAID 1) while #3 gives only > >17MB/s. I'd expect #3 to be about x2 the performance of #1. > > > > >The arrays are configured with "write-thru" write policy, "adaptive" > >read policy, and "cachedio" cache policy. > > In LSI terms, "write-thru" means, "write cache is turned off". With > that set, performance becomes very consistently describable as "poor", > as your tests demonstrate. Linux can get around this a little bit in > benchmarks by using larger I/O sizes than FreeBSD (FreeBSD is limited to > 128K max, while Linux is not). If you don't have the battery backup, "write-thru" might be a bit of a problem :) > These are very speedy cards once you put them into their intended > configuration. With some decent SCSI disks and a PCI-X bus, it > performs quite well. However, I'm actually kinda surprised that the > card works at all in your 5V slot. Yeah, but we have a few of these mobos so figured we might as well reuse them. And, we got the 320-2 for cheap. According to http://lsionline2.lsil.com/esupport/esupportlsi/consumer/esupport.asp?hotid=bf88d26d-7205-4bcd-a542-d2a9b4af2b4e&number=1&nShowFacts=&nShowCause=&nShowChange=&nShowAddInfo=&activepage=statement.asp&bForceMatch=False&strCurrentSymptom=&searchtype=normal&searchclass=QuickSearch&bnewsession=True&selecttype=match: Q. Will a 64-bit PCI MegaRAID controller work in a 32-bit PCI slot (or vise versa)? Will a 64-bit controller work in a PCI-X slot (or vise versa)? A. Yes. If the controller fits in the PCI or PCI-X slot, the MegaRAID controller will operate. However, the performance of a 64-bit controller will be degraded when placed in a 32-bit slot. -- albert chin (china@thewrittenword.com)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20060929195941.GD53879>