From owner-freebsd-current Thu Dec 16 8:37: 8 1999 Delivered-To: freebsd-current@freebsd.org Received: from dozer.skynet.be (dozer.skynet.be [195.238.2.36]) by hub.freebsd.org (Postfix) with ESMTP id 8464114CC9 for ; Thu, 16 Dec 1999 08:36:54 -0800 (PST) (envelope-from brad@shub-internet.org) Received: from [195.238.1.121] (brad.techos.skynet.be [195.238.1.121]) by dozer.skynet.be (8.9.3/odie-relay-v1.0) with ESMTP id RAA27216; Thu, 16 Dec 1999 17:36:45 +0100 (MET) Mime-Version: 1.0 X-Sender: blk@foxbert.skynet.be Message-Id: In-Reply-To: <14425.2778.943367.365945@trooper.velocet.net> References: <14425.2778.943367.365945@trooper.velocet.net> Date: Thu, 16 Dec 1999 17:35:28 +0100 To: David Gilbert , freebsd-current@FreeBSD.ORG From: Brad Knowles Subject: Re: AMI MegaRAID datapoint. Content-Type: text/plain; charset="us-ascii" ; format="flowed" Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG At 10:52 AM -0500 1999/12/16, David Gilbert wrote: > Now... using vinum and either the 2940U2W (Adaptec LVD) or the TekRAM > (NCR) LVD (using the sym0 device) gives 30 to 35 M/s under RAID-5. That's really interesting, because there are at least two or three outstanding bugs in the vinum RAID-5 implementation that have prevented me from successfully benchmarking it (see ). Have you been using rawio? Have you made any attempt to try duplicating some of the sorts of benchmarks I've done, available at ? > This is impressive and subject to the bug that I mentioned in -STABLE > which still hasn't been found. Which one is this? > The AMI MegaRAID 1400 delivers between 16.5 and 19 M/s (the 19M/s > value is somewhat contrived --- using 8 bonnies in parrallel and then > summing their results --- which is not 100% valid)... but the MegaRAID > appears to be stable. If you look at the page I mentioned, you'll see that my best sustained speed with a vinum 4-way stripe on IBM 10kRPM 9LZX drives attached to an Adaptec 2940UW controller was about 19MB/s sequential read (anywhere from four to 128 processes), 16.5MB/s random read (64-256 processes), 14MB/s sequential write (16 processes), and 15MB/s random write (64-256 processes). My best performance with a DPT SmartRAID IV in a 4-way stripe with the same disks was 16.5MB/s sequential read (4 processes), 7.5MB/s random read (pretty much regardless of how many processes), 17MB/s sequential write (256 processes), and 6MB/s (independent of the number of processes). I did not attempt to benchmark DPT SmartRAID IV performance under RAID-5. I'd be very interested to see more extensive benchmarking of this configuration. In addition to my page above, I'd recommend you look at and , and see which of these you can throw at your system. With luck, in about a month or so, I should be getting a new server in with 1GB RAM, 450Mhz Pentium III w/ 1MB L2 cache, a DPT SmartRAID V controller with 256MB ECC cache, and eight Fujitsu MAE3182LC 7200RPM 18GB drives for RAID-5 configuration on a single SCSI bus, for our new anonymous ftp server. I know this isn't an ideal configuration (I shouldn't have more than four devices on a SCSI bus, and I should be using faster drives with lower latency), but it will be very interesting to test out this configuration with 3.4-RELEASE and what should hopefully be stable DPT SmartRAID V/VI drivers by then. I plan on beating the crap out of this machine before it goes online. ;-) -- Brad Knowles Your mouse has moved. Windows NT must be restarted for the change to take effect. Reboot now? [ OK ] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message