From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset=US-ASCII From: Daniel Phillips Subject: Re: [PATCH] MAX_READAHEAD gives doubled throuput Date: Sat, 28 Jul 2001 04:08:17 +0200 References: <200107280144.DAA25730@mailb.telia.com> In-Reply-To: <200107280144.DAA25730@mailb.telia.com> MIME-Version: 1.0 Message-Id: <0107280408170Z.00285@starship> Content-Transfer-Encoding: 7BIT Sender: owner-linux-mm@kvack.org Return-Path: To: Roger Larsson , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org List-ID: On Saturday 28 July 2001 03:40, Roger Larsson wrote: > Hi all, > > Got wondering why simultaneous streaming is so much slower than > normal... > > Are there any reasons nowadays why we should not attempt to read > ahead more than 31 pages at once? > > 31 pages equals 0.1 MB, it is read from the HD in 4 ms => very close > to the average access times. Resulting in a maximum of half the > possible speed. > > With this patch copy and diff throughput are increased from 14 > respective 11 MB/s to 27 and 28 !!! Wheeeeee! Out of interest, what are the numbers for 2.4.7 vs 2.4.8-pre1 ? -- Daniel -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/