From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-f198.google.com (mail-ob0-f198.google.com [209.85.214.198]) by kanga.kvack.org (Postfix) with ESMTP id 7E84E6B0253 for ; Fri, 17 Jun 2016 08:28:22 -0400 (EDT) Received: by mail-ob0-f198.google.com with SMTP id at7so1316137obd.3 for ; Fri, 17 Jun 2016 05:28:22 -0700 (PDT) Received: from mail-it0-x242.google.com (mail-it0-x242.google.com. [2607:f8b0:4001:c0b::242]) by mx.google.com with ESMTPS id u74si5132898itc.107.2016.06.17.05.28.19 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 17 Jun 2016 05:28:19 -0700 (PDT) Received: by mail-it0-x242.google.com with SMTP id f6so1834748ith.1 for ; Fri, 17 Jun 2016 05:28:19 -0700 (PDT) Subject: Re: [PATCH] zram: update zram to use zpool References: <20160615231732.GJ17127@bbox> From: "Austin S. Hemmelgarn" Message-ID: <8ffd0aab-1adb-17a9-3055-ad60c31f8eb6@gmail.com> Date: Fri, 17 Jun 2016 08:28:14 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Vitaly Wool , Minchan Kim Cc: Geliang Tang , Nitin Gupta , Sergey Senozhatsky , Dan Streetman , LKML , Linux-MM On 2016-06-17 04:30, Vitaly Wool wrote: > Hi Minchan, > > On Thu, Jun 16, 2016 at 1:17 AM, Minchan Kim wrote: >> On Wed, Jun 15, 2016 at 10:42:07PM +0800, Geliang Tang wrote: >>> Change zram to use the zpool api instead of directly using zsmalloc. >>> The zpool api doesn't have zs_compact() and zs_pool_stats() functions. >>> I did the following two things to fix it. >>> 1) I replace zs_compact() with zpool_shrink(), use zpool_shrink() to >>> call zs_compact() in zsmalloc. >>> 2) The 'pages_compacted' attribute is showed in zram by calling >>> zs_pool_stats(). So in order not to call zs_pool_state() I move the >>> attribute to zsmalloc. >>> >>> Signed-off-by: Geliang Tang >> >> NACK. >> >> I already explained why. >> http://lkml.kernel.org/r/20160609013411.GA29779@bbox > > This is a fair statement, to a certain extent. I'll let Geliang speak > for himself but I am personally interested in this zram extension > because I want it to work on MMU-less systems. zsmalloc can not handle > that, so I want to be able to use zram over z3fold. I concur with this. It's also worth pointing out that people can and do use zram for things other than swap, so the assumption that zswap is a viable alternative is not universally correct. In my case for example, I use it on a VM host for temporary storage for transient SSI VM's. Making it more deterministic would be seriously helpful in this case, as it would mean I can more precisely provision resources on this particular system, and could better account for latencies in the testing these transient VM's are used for. -- 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/ . Don't email: email@kvack.org