From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4060BP2XYjzF1sm for ; Thu, 22 Mar 2018 06:25:17 +1100 (AEDT) Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w2LJMXvU078850 for ; Wed, 21 Mar 2018 15:25:14 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0b-001b2d01.pphosted.com with ESMTP id 2guwg9g3y2-1 (version=TLSv1.2 cipher=AES256-SHA256 bits=256 verify=NOT) for ; Wed, 21 Mar 2018 15:25:14 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 21 Mar 2018 19:25:11 -0000 From: Mike Rapoport To: Jonathan Corbet Cc: Andrey Ryabinin , Richard Henderson , Ivan Kokshaysky , Matt Turner , Tony Luck , Fenghua Yu , Ralf Baechle , James Hogan , Michael Ellerman , Alexander Viro , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, kasan-dev@googlegroups.com, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@linux-mips.org, linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Mike Rapoport Subject: [PATCH 29/32] docs/vm: zsmalloc.txt: convert to ReST format Date: Wed, 21 Mar 2018 21:22:45 +0200 In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com> References: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com> Message-Id: <1521660168-14372-30-git-send-email-rppt@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Signed-off-by: Mike Rapoport --- Documentation/vm/zsmalloc.txt | 60 ++++++++++++++++++++++++++----------------- 1 file changed, 36 insertions(+), 24 deletions(-) diff --git a/Documentation/vm/zsmalloc.txt b/Documentation/vm/zsmalloc.txt index 64ed63c..6e79893 100644 --- a/Documentation/vm/zsmalloc.txt +++ b/Documentation/vm/zsmalloc.txt @@ -1,5 +1,8 @@ +.. _zsmalloc: + +======== zsmalloc --------- +======== This allocator is designed for use with zram. Thus, the allocator is supposed to work well under low memory conditions. In particular, it @@ -31,40 +34,49 @@ be mapped using zs_map_object() to get a usable pointer and subsequently unmapped using zs_unmap_object(). stat ----- +==== With CONFIG_ZSMALLOC_STAT, we could see zsmalloc internal information via -/sys/kernel/debug/zsmalloc/. Here is a sample of stat output: +``/sys/kernel/debug/zsmalloc/``. Here is a sample of stat output:: -# cat /sys/kernel/debug/zsmalloc/zram0/classes + # cat /sys/kernel/debug/zsmalloc/zram0/classes class size almost_full almost_empty obj_allocated obj_used pages_used pages_per_zspage - .. - .. + ... + ... 9 176 0 1 186 129 8 4 10 192 1 0 2880 2872 135 3 11 208 0 1 819 795 42 2 12 224 0 1 219 159 12 4 - .. - .. + ... + ... + +class + index +size + object size zspage stores +almost_empty + the number of ZS_ALMOST_EMPTY zspages(see below) +almost_full + the number of ZS_ALMOST_FULL zspages(see below) +obj_allocated + the number of objects allocated +obj_used + the number of objects allocated to the user +pages_used + the number of pages allocated for the class +pages_per_zspage + the number of 0-order pages to make a zspage -class: index -size: object size zspage stores -almost_empty: the number of ZS_ALMOST_EMPTY zspages(see below) -almost_full: the number of ZS_ALMOST_FULL zspages(see below) -obj_allocated: the number of objects allocated -obj_used: the number of objects allocated to the user -pages_used: the number of pages allocated for the class -pages_per_zspage: the number of 0-order pages to make a zspage +We assign a zspage to ZS_ALMOST_EMPTY fullness group when n <= N / f, where -We assign a zspage to ZS_ALMOST_EMPTY fullness group when: - n <= N / f, where -n = number of allocated objects -N = total number of objects zspage can store -f = fullness_threshold_frac(ie, 4 at the moment) +* n = number of allocated objects +* N = total number of objects zspage can store +* f = fullness_threshold_frac(ie, 4 at the moment) Similarly, we assign zspage to: - ZS_ALMOST_FULL when n > N / f - ZS_EMPTY when n == 0 - ZS_FULL when n == N + +* ZS_ALMOST_FULL when n > N / f +* ZS_EMPTY when n == 0 +* ZS_FULL when n == N -- 2.7.4