From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id C931A9000BD for ; Thu, 15 Sep 2011 18:27:35 -0400 (EDT) MIME-Version: 1.0 Message-ID: <504b4342-e6b0-4544-b81c-ca41240ac5bf@default> Date: Thu, 15 Sep 2011 15:27:07 -0700 (PDT) From: Dan Magenheimer Subject: RE: [PATCH v2 0/3] staging: zcache: xcfmalloc support References: <1315404547-20075-1-git-send-email-sjenning@linux.vnet.ibm.com> <20110909203447.GB19127@kroah.com> <4E6ACE5B.9040401@vflare.org> <4E6E18C6.8080900@linux.vnet.ibm.com> <4E6EB802.4070109@vflare.org> <4E6F7DA7.9000706@linux.vnet.ibm.com> <4E6FC8A1.8070902@vflare.org> <4E72284B.2040907@linux.vnet.ibm.com> <075c4e4c-a22d-47d1-ae98-31839df6e722@default> <4E725109.3010609@linux.vnet.ibm.com 1316125062.16137.80.camel@nimitz> In-Reply-To: <1316125062.16137.80.camel@nimitz> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Dave Hansen , Seth Jennings Cc: Nitin Gupta , Greg KH , gregkh@suse.de, devel@driverdev.osuosl.org, cascardo@holoscopio.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, brking@linux.vnet.ibm.com, rcj@linux.vnet.ibm.com > From: Dave Hansen [mailto:dave@linux.vnet.ibm.com] > Subject: Re: [PATCH v2 0/3] staging: zcache: xcfmalloc support >=20 > On Thu, 2011-09-15 at 14:24 -0500, Seth Jennings wrote: > > How would you suggest that I measure xcfmalloc performance on a "very > > large set of workloads". I guess another form of that question is: How > > did xvmalloc do this? >=20 > Well, it didn't have a competitor, so this probably wasn't done. :) >=20 > I'd like to see a microbenchmarky sort of thing. Do a million (or 100 > million, whatever) allocations, and time it for both allocators doing > the same thing. You just need to do the *same* allocations for both. One suggestion: We already know xvmalloc sucks IF the workload has poor compression for most pages. We are looking to understand if xcfmalloc is [very**N] bad when xvmalloc is good. So please measure BIG-NUMBER allocations where compression is known to be OK on average (which is, I think, a large fraction of workloads), rather than workloads where xvmalloc already sucks. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org