From owner-freebsd-arch@FreeBSD.ORG Tue Mar 12 23:01:39 2013 Return-Path: Delivered-To: arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 526828AB for ; Tue, 12 Mar 2013 23:01:39 +0000 (UTC) (envelope-from jhs@berklix.com) Received: from flat.berklix.org (flat.berklix.org [83.236.223.115]) by mx1.freebsd.org (Postfix) with ESMTP id B4FA5EE0 for ; Tue, 12 Mar 2013 23:01:38 +0000 (UTC) Received: from mart.js.berklix.net (p57BCFE7C.dip.t-dialin.net [87.188.254.124]) (authenticated bits=128) by flat.berklix.org (8.14.5/8.14.5) with ESMTP id r2CN0vLf006836; Wed, 13 Mar 2013 00:00:57 +0100 (CET) (envelope-from jhs@berklix.com) Received: from fire.js.berklix.net (fire.js.berklix.net [192.168.91.41]) by mart.js.berklix.net (8.14.3/8.14.3) with ESMTP id r2CN1KHE025314; Wed, 13 Mar 2013 00:01:20 +0100 (CET) (envelope-from jhs@berklix.com) Received: from fire.js.berklix.net (localhost [127.0.0.1]) by fire.js.berklix.net (8.14.4/8.14.4) with ESMTP id r2CN0vHY068859; Wed, 13 Mar 2013 00:01:02 +0100 (CET) (envelope-from jhs@fire.js.berklix.net) Message-Id: <201303122301.r2CN0vHY068859@fire.js.berklix.net> To: arch@freebsd.org Subject: IBM Active Memory Expansion = compression in the idle loop. From: "Julian H. Stacey" Organization: http://berklix.com BSD Linux Unix Consultancy, Munich Germany User-agent: EXMH on FreeBSD http://www.berklix.com/free/ X-URL: http://www.berklix.com/~jhs/cv/ Date: Wed, 13 Mar 2013 00:00:57 +0100 Sender: jhs@berklix.com Cc: Wolfgang Stief X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Mar 2013 23:01:39 -0000 Hi arch@freebsd.org cc Wolfgang Stief FYI Just mentioning this for general interest: At an IBM presentation to SAGE (Sys Admin Guild) in Munich yesterday 2013-03-12, IBM mentioned "Active Memory Expansion' Which is memory compression using spare CPU cycles, IBM tend to have more spare CPU cycles as sometimes software is only licenced for so many CPUs, & other CPUs are idling. Interesting idea, though presumably less useful for FreeBSD (& Linux etc) where we dont generaly have those licensed binary per CPU issues, so perhaps less spare unused CPU cycles. http://ixquick.com (search engine) found this: https://www.ibm.com/developerworks/wikis/display/WikiPtype/IBM+Active+Memory+Expansion The projector slides were some German, some American, some PDFs of the evening's 3 presentations will be linked here in a couple of days I expect. http://www.guug.de/lokal/muenchen/index.html I didnt ask (but wondered) what sort of loads would have lots of flabby data that could be easily cheaply compressed. IBM were obviously focused on business databases (I wonder if they still ahve fixed length records ?) Presumably less interesting to compress RAM data if a CPU is working on eg geographic topography data or some such ? I also didnt ask if it was patented (in case any think "great idea" & rush off to code :-) Apparently IBM's Linux dev drivers are all public source, not binary only, (but presumably FSF licence), but I think this IBM Active Memory Expansion (AME) is only (as per URL above) for * HMC: V7R7.1.0.0 * eFW: 7.1 * AIX: 6.1 TL4 SP2 & not for Linux, so probably there's no public source to browse. Anyway, seemed an odd new idea to me. Cheers, Julian -- Julian Stacey, BSD Unix Linux C Sys Eng Consultant, Munich http://berklix.com Reply below not above, like a play script. Indent old text with "> ". Send plain text. No quoted-printable, HTML, base64, multipart/alternative.