From mboxrd@z Thu Jan 1 00:00:00 1970 From: "JaniD++" Subject: RAID0 performance question Date: Sat, 26 Nov 2005 15:04:37 +0100 Message-ID: <015c01c5f292$57e0e270$0400a8c0@dcccs> References: <437E2CB6.2030903@xss.co.at> <17282.22120.327672.720044@cse.unsw.edu.au> <20051122220531.GU26862@skl-net.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hello list, I have searching the bottleneck of my system, and found something what i cant cleanly understand. I have use NBD with 4 disk nodes. (raidtab is the bottom of mail) The cat /dev/nb# >/dev/null makes ~ 350 Mbit/s on each nodes. The cat /dev/nb0 + nb1 + nb2 + nb3 in one time parallel makes ~ 780-800 Mbit/s. - i think this is my network bottleneck. But the cat /dev/md31 >/dev/null (RAID0, the sum of 4 nodes) only makes ~450-490 Mbit/s, and i dont know why.... Somebody have an idea? :-) (the nb31,30,29,28 only possible mirrors) Thanks Janos raiddev /dev/md1 raid-level 1 nr-raid-disks 2 chunk-size 32 persistent-superblock 1 device /dev/nb0 raid-disk 0 device /dev/nb31 raid-disk 1 failed-disk /dev/nb31 raiddev /dev/md2 raid-level 1 nr-raid-disks 2 chunk-size 32 persistent-superblock 1 device /dev/nb1 raid-disk 0 device /dev/hb30 raid-disk 1 failed-disk /dev/nb30 raiddev /dev/md3 raid-level 1 nr-raid-disks 2 chunk-size 32 persistent-superblock 1 device /dev/nb2 raid-disk 0 device /dev/nb29 raid-disk 1 failed-disk /dev/nb29 raiddev /dev/md4 raid-level 1 nr-raid-disks 2 chunk-size 32 persistent-superblock 1 device /dev/nb3 raid-disk 0 device /dev/nb28 raid-disk 1 failed-disk /dev/nb28 raiddev /dev/md31 raid-level 0 nr-raid-disks 4 chunk-size 32 persistent-superblock 1 device /dev/md1 raid-disk 0 device /dev/md2 raid-disk 1 device /dev/md3 raid-disk 2 device /dev/md4 raid-disk 3