Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751971AbXE3FUI (ORCPT ); Wed, 30 May 2007 01:20:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750932AbXE3FT5 (ORCPT ); Wed, 30 May 2007 01:19:57 -0400 Received: from an-out-0708.google.com ([209.85.132.248]:61491 "EHLO an-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750872AbXE3FT4 (ORCPT ); Wed, 30 May 2007 01:19:56 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Plu1DNq2VxL536Ew7VHDvyHhpl0rn5Uevl3Eww5BeI6j+YpVCTjTLkUUgpYJ6L+3iRuHm2Zdq81iGvlCuTnDHXFi/zDgMDcZ58DUrH/1Ae0EfOz24l69KQ/4pTYaNRGIlUogpR5bVzR/wX0TNfTDOIDP1jXpUmWRw8rxp41441o= Message-ID: <4cefeab80705292219x31956353r308b0ed0a052071@mail.gmail.com> Date: Wed, 30 May 2007 10:49:45 +0530 From: "Nitin Gupta" To: "Daniel Hazelton" Subject: Re: [RFC] LZO de/compression support - take 6 Cc: "Bret Towe" , lkml , linux-mm-cc@laptop.org, linuxcompressed-devel@lists.sourceforge.net, "Andrew Morton" , "Richard Purdie" , "Satyam Sharma" In-Reply-To: <200705291932.04255.dhazelton@enter.net> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <4cefeab80705280734i37df1742k6738cd4200813684@mail.gmail.com> <4cefeab80705282258p570c649aja5a60b82f63c2440@mail.gmail.com> <200705291932.04255.dhazelton@enter.net> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1809 Lines: 41 On 5/30/07, Daniel Hazelton wrote: > I just noticed a bug in my testbed/benchmarking code. It's fixed, but I > decided to compare version 6 of the code against the *unsafe* decompressor > again. The results of the three runs I've put it through after changing it to > compare against the unsafe decompressor were startling. `Tiny's` compressor > is still faster - I've seen it be rated up to 3% faster. The decompressor, > OTOH, when compared to the unsafe version (which is the comparison that > started me on this binge of hacking), is more than 7% worse. About 11% slower > on the original test against a C source file, and about 6% slower for random > data. Unsafe vs safe is within 10%. Its okay. > However, looking at the numbers involved, I can't see a reason to keep > the unsafe version around - the percentages look worse than they are - from 1 > to 3 microseconds. Not just numbers. Most of applications cannot afford to use unsafe versions anyway (like fs people). (well, the compressed-cache people might want those extra > usecs - but the difference will never be noticeable anywhere outside the > kernel) > > DRH > compressed cache people require every single percent of that performance. For now, ccaching is not ready for mainline (many things need to be done). So, till then I will keep off the unsafe version. If ever compressed caching is on its way to mainline _then_ I will try and add back the unsafe version. But I see no other project that really cares about unsafe version so it's okay to keep it off. - Nitin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/