From owner-freebsd-performance@FreeBSD.ORG Mon Jun 2 08:08:40 2003 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 160E237B401 for ; Mon, 2 Jun 2003 08:08:40 -0700 (PDT) Received: from wg.pu.ru (wg.pu.ru [193.124.85.219]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8862F43F85 for ; Mon, 2 Jun 2003 08:08:38 -0700 (PDT) (envelope-from ahk@spb.edu) Received: from ahk-work (ank.pu.ru [194.58.104.203]) by wg.pu.ru (8.9.1a/8.9.1) with ESMTP id PAA10784; Mon, 2 Jun 2003 15:08:33 GMT From: "Aleksey Kuznetsov" Organization: VTC SPbU To: Michael Conlen Date: Mon, 02 Jun 2003 19:08:25 +0400 MIME-Version: 1.0 Message-ID: <3EDBA0A9.21063.33B9D6B9@localhost> Priority: normal In-reply-to: <3EDB67B1.2040609@obfuscated.net> X-mailer: Pegasus Mail for Windows (v4.02a) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Content-description: Mail message body Content-Transfer-Encoding: 7BIT cc: freebsd-performance@freebsd.org Subject: Re: copy 150G over 100Mbit X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list Reply-To: ahk@spb.edu List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 Jun 2003 15:08:40 -0000 On 2 Jun 2003 at 11:05, Michael Conlen wrote: > 12.5MBytes/sec = 750 MBytes/min = 4500 MBytes/hour. 12,5MBytes/sec = 750 MBytes/min = 45000 Mbytes/hour ==== > > Two problems, protocol overhead and disk speed. > > How fast can you read off that IDE system? Try tarring the filesystem > and dumping it to /dev/null. If you can't get 12.5MBytes/sec then > don't look to the network first.You should consider the size of your > files. Sure your disks can move data fast, however if you have lots > and lots of really small files your disks are going to be seeking all > the time and reading very little of it. If your moving one large file > there's less seek and more read. Also with lots of small files > whatever protocol you use will have more overhead to eat more of your > network bandwith. The difference can be an order of magnitude in disk > throughput on reads. > > Over the network you will end up with all kinds of overhead for > various protocols. NFS isn't the fastest thing in the world. Rsync has > it's uses, but I don't think this is one of them. > > Consider using cpio over the network. Quick tests show that cpio gets > better performance than tar by a long shot. > > Another consideration might be to move the entire filesystem. If you > create identical sized partitions on each system, instead of mounting > them just copy the whole filesystem across using ssh or rsh. I haven't > tried this on FreeBSD but it shouldn't be to hard to get working. The > idea being that you read from /dev/ad0s1f on one box and write to > /dev/ad0s1f on the other. Something like > > dd if=/dev/ad0s1f | ssh hostname 'dd of=/dev/ad0s1f' > > You can try playing with the bs parameter to get optimal read/write > speeds. A quick test on my system shows that the disk throughput > increases as the block size increases up to about 8k from > 4.5MBytes/sec at 512 to 12MBytes/sec at 8k. On a RAID setup it's > likely to be larger. > > You may be able to dump to a larger partition on the destination > system though the extra space would go unused. I don't have a good way > to test this here. > > -- > Michael Conlen > > > Achim Patzner wrote: > > >Am 02.06.2003 16:23 Uhr schrieb "Damir Horvat" unter > >: > > > > > >>I need to copy ~150Gbytes over switched 100Mbit network to new > >>machine (in max 7-8 hours). > >> > >>Source machine (IDE RAID 5) is in production, iostat shows average > >>transfer of 8-9Mbytes/sec. Destination box is FBC RAID 10. > >> > >> > > > >Excuse me, but what would you expect using a 100 M*bit*/s network > >connection? > > > > > >Achim > > > >_______________________________________________ > >freebsd-performance@freebsd.org mailing list > >http://lists.freebsd.org/mailman/listinfo/freebsd-performance > >To unsubscribe, send any mail to > >"freebsd-performance-unsubscribe@freebsd.org" > > > > > > > _______________________________________________ > freebsd-performance@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-performance > To unsubscribe, send any mail to > "freebsd-performance-unsubscribe@freebsd.org"