From owner-freebsd-questions Thu Oct 30 18:01:51 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id SAA01278 for questions-outgoing; Thu, 30 Oct 1997 18:01:51 -0800 (PST) (envelope-from owner-freebsd-questions) Received: from bastuba.partitur.se (bastuba.partitur.se [193.219.246.194]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id SAA01228 for ; Thu, 30 Oct 1997 18:01:21 -0800 (PST) (envelope-from girgen@partitur.se) Received: from partitur.se (dialup165-2-54.swipnet.se [130.244.165.118]) by bastuba.partitur.se (8.8.5/8.8.5) with ESMTP id DAA06823 for ; Fri, 31 Oct 1997 03:00:32 +0100 (CET) Message-ID: <34593BC3.41335BA2@partitur.se> Date: Fri, 31 Oct 1997 03:00:35 +0100 From: Palle Girgensohn Organization: Partitur X-Mailer: Mozilla 4.03b8 [en] (X11; I; FreeBSD 2.2-STABLE i386) MIME-Version: 1.0 To: freebsd-questions@freebsd.org Subject: rdump and blocksize? Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@freebsd.org X-Loop: FreeBSD.org Precedence: bulk Hi all! I've been browsing though the mail archive looking for tips on setting a good blocksize for rdump. My problem is the same as for many others: rdump is slow, around 48KB/s. I have checked the network cards, and troughput is very good otherwise (using for example rcp). Some recommended raising the blocksize, which seems like the right thing to do. Only, 64 KB is the limit. I don't see it help very much. Often 10KB or 32 KB were recommended as good values. So here's my main quiestion: Do I have to fine tune the blocksize to some magic value where it's synced with network & tape drive, or is bigger blocks == faster? I tried 10 KB, and didn't see any difference. And the -B, is it only for calculating tape usage? The tape is a Seagate using Travan TR-4, cartridge and compression, so density is not very interresting, I presume. Thanks for any help in clarifying, and speeding up, my rdumps. Regards, Palle