From mboxrd@z Thu Jan 1 00:00:00 1970 From: James A. Sutherland Subject: Re: Want to allocate almost all the memory with no swap Date: Thu, 19 Apr 2001 17:10:31 +0100 Message-ID: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Sender: owner-linux-mm@kvack.org Return-Path: To: Simon Derr Cc: linux-mm@kvack.org List-ID: On Thu, 19 Apr 2001 17:58:38 +0200 (MEST), you wrote: >On Thu, 19 Apr 2001, James A. Sutherland wrote: > >> On Thu, 19 Apr 2001 17:39:23 +0200 (MEST), you wrote: >> >> >Hi, >> > >> >I'm currently trying to run a high-performance bench on a cluster of PCs >> >under Linux. This bench is the Linpack test, and needs a lot of memory to >> >store a matrix of numbers. Linpack needs to allocate as much as 240 Megs >> >on a machine that has 256 Megs of RAM, but I have to be sure that the >> >memory used by linpack will never be swapped on the disk. >> >> Call mlockall() to lock all your memory into physical RAM - there's a >> flag to set which ensures all your future allocations are locked as >> well. You should be left with 16 Mb of physical RAM free, plus swap, >> so you should be able to do this as long as the machine isn't too >> heavily loaded at the time - no running Netscape during benchmarks :-) > >Well, I have removed as many processes deamons as I could, and there are >not many left. >But under both 2.4.2 and 2.2.17 (with swap on)I get, when I run my >program: > >mlockall: Cannot allocate memory Hrm? Can you trim the consumption a bit - try cutting a big chunk out, like 64 Mb, and see if it works then? James. -- 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.eu.org/Linux-MM/