From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukas Kolbe Subject: RE: After memory pressure: can't read from tape anymore Date: Sun, 05 Dec 2010 11:44:49 +0100 Message-ID: <1291545889.2814.2882.camel@larosa> References: <1290971729.2814.13.camel@larosa> <1291123886.2181.1347.camel@quux.techfak.uni-bielefeld.de> <4CF521DE.7020800@panasas.com> <4CF52A03.2000704@panasas.com> <4CF53349.10509@panasas.com> <1291196400.2814.34.camel@larosa> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from smarthost.TechFak.Uni-Bielefeld.DE ([129.70.137.17]:50547 "EHLO smarthost.TechFak.Uni-Bielefeld.DE" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754601Ab0LEKox (ORCPT ); Sun, 5 Dec 2010 05:44:53 -0500 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Kai Makisara Cc: "Desai, Kashyap" , Boaz Harrosh , "linux-scsi@vger.kernel.org" Am Donnerstag, den 02.12.2010, 22:25 +0200 schrieb Kai Makisara: > P.S. Why is it necessary to use 2 MB blocks? Some people say that it is > the optimal block size for some current tape drives. I really couldn't care less about blocksizes, but it seems to be that it's impossible to reach high LTO4 write-speeds with lower blocksizes; tests show that >100MiB/s are not possible with blocksizes around 64KB to 512KB (from memory), so: the bigger the blocksize, the higher the writing speed. I suppose this gets even more critical with LTO5 drives. -- Lukas