From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f44.google.com (mail-pa0-f44.google.com [209.85.220.44]) by kanga.kvack.org (Postfix) with ESMTP id 910816B0038 for ; Wed, 8 Jul 2015 07:32:47 -0400 (EDT) Received: by pabvl15 with SMTP id vl15so130327373pab.1 for ; Wed, 08 Jul 2015 04:32:47 -0700 (PDT) Received: from mail-pa0-x22c.google.com (mail-pa0-x22c.google.com. [2607:f8b0:400e:c03::22c]) by mx.google.com with ESMTPS id dd8si3670103pdb.122.2015.07.08.04.32.46 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 08 Jul 2015 04:32:46 -0700 (PDT) Received: by pactm7 with SMTP id tm7so130431058pac.2 for ; Wed, 08 Jul 2015 04:32:46 -0700 (PDT) From: Sergey Senozhatsky Subject: [PATCH v7 0/7] mm/zsmalloc: introduce automatic pool compaction Date: Wed, 8 Jul 2015 20:31:46 +0900 Message-Id: <1436355113-12417-1-git-send-email-sergey.senozhatsky@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky , Sergey Senozhatsky Hello, Hopefully the final version. This patch set tweaks compaction and makes it possible to trigger pool compaction automatically when system is getting low on memory. zsmalloc in some cases can suffer from a notable fragmentation and compaction can release some considerable amount of memory. The problem here is that currently we fully rely on user space to perform compaction when needed. However, performing zsmalloc compaction is not always an obvious thing to do. For example, suppose we have a `idle' fragmented (compaction was never performed) zram device and system is getting low on memory due to some 3rd party user processes (gcc LTO, or firefox, etc.). It's quite unlikely that user space will issue zpool compaction in this case. Besides, user space cannot tell for sure how badly pool is fragmented; however, this info is known to zsmalloc and, hence, to a shrinker. v7: -- minor coding styles cleanups and tweaks v6: -- use new zs_pool stats API (Minchan) v5: -- account freed pages correctly v4: address review notes (Minchan) -- do not abort __zs_compact() quickly (Minchan) -- switch zsmalloc compaction to operate in terms of freed pages -- micro-optimize zs_can_compact() (Minchan) v3: -- drop almost_empty waterline adjustment patch (Minchan) -- do not hold class->lock for the entire compaction period (Minchan) v2: -- use a slab shrinker instead of triggering compaction from zs_free (Minchan) Sergey Senozhatsky (7): zsmalloc: drop unused variable `nr_to_migrate' zsmalloc: always keep per-class stats zsmalloc: introduce zs_can_compact() function zsmalloc: cosmetic compaction code adjustments zsmalloc/zram: introduce zs_pool_stats api zsmalloc: account the number of compacted pages zsmalloc: use shrinker to trigger auto-compaction Documentation/blockdev/zram.txt | 3 +- drivers/block/zram/zram_drv.c | 15 +-- drivers/block/zram/zram_drv.h | 1 - include/linux/zsmalloc.h | 6 ++ mm/zsmalloc.c | 204 ++++++++++++++++++++++++++++------------ 5 files changed, 161 insertions(+), 68 deletions(-) -- 2.4.5 -- 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