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Huang Ying e39bb6be9f NUMA Balancing: add page promotion counter 
Patch series "NUMA balancing: optimize memory placement for memory tiering system", v13

With the advent of various new memory types, some machines will have
multiple types of memory, e.g.  DRAM and PMEM (persistent memory).  The
memory subsystem of these machines can be called memory tiering system,
because the performance of the different types of memory are different.

After commit c221c0b030 ("device-dax: "Hotplug" persistent memory for
use like normal RAM"), the PMEM could be used as the cost-effective
volatile memory in separate NUMA nodes.  In a typical memory tiering
system, there are CPUs, DRAM and PMEM in each physical NUMA node.  The
CPUs and the DRAM will be put in one logical node, while the PMEM will
be put in another (faked) logical node.

To optimize the system overall performance, the hot pages should be
placed in DRAM node.  To do that, we need to identify the hot pages in
the PMEM node and migrate them to DRAM node via NUMA migration.

In the original NUMA balancing, there are already a set of existing
mechanisms to identify the pages recently accessed by the CPUs in a node
and migrate the pages to the node.  So we can reuse these mechanisms to
build the mechanisms to optimize the page placement in the memory
tiering system.  This is implemented in this patchset.

At the other hand, the cold pages should be placed in PMEM node.  So, we
also need to identify the cold pages in the DRAM node and migrate them
to PMEM node.

In commit 26aa2d199d ("mm/migrate: demote pages during reclaim"), a
mechanism to demote the cold DRAM pages to PMEM node under memory
pressure is implemented.  Based on that, the cold DRAM pages can be
demoted to PMEM node proactively to free some memory space on DRAM node
to accommodate the promoted hot PMEM pages.  This is implemented in this
patchset too.

We have tested the solution with the pmbench memory accessing benchmark
with the 80:20 read/write ratio and the Gauss access address
distribution on a 2 socket Intel server with Optane DC Persistent Memory
Model.  The test results shows that the pmbench score can improve up to
95.9%.

This patch (of 3):

In a system with multiple memory types, e.g.  DRAM and PMEM, the CPU
and DRAM in one socket will be put in one NUMA node as before, while
the PMEM will be put in another NUMA node as described in the
description of the commit c221c0b030 ("device-dax: "Hotplug"
persistent memory for use like normal RAM").  So, the NUMA balancing
mechanism will identify all PMEM accesses as remote access and try to
promote the PMEM pages to DRAM.

To distinguish the number of the inter-type promoted pages from that of
the inter-socket migrated pages.  A new vmstat count is added.  The
counter is per-node (count in the target node).  So this can be used to
identify promotion imbalance among the NUMA nodes.

Link: https://lkml.kernel.org/r/20220301085329.3210428-1-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20220221084529.1052339-1-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20220221084529.1052339-2-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Tested-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: zhongjiang-ali <zhongjiang-ali@linux.alibaba.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:09 -07:00
arch powerpc/fadump: opt out from freeing pages on cma activation failure 2022-03-22 15:57:09 -07:00
block fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
certs certs: Fix build error when CONFIG_MODULE_SIG_KEY is empty 2022-01-23 00:08:44 +09:00
crypto crypto: af_alg - get rid of alg_memory_allocated 2022-02-15 14:29:04 +00:00
Documentation mm: hugetlb: free the 2nd vmemmap page associated with each HugeTLB page 2022-03-22 15:57:08 -07:00
drivers mm/hwpoison: avoid the impact of hwpoison_filter() return value on mce handler 2022-03-22 15:57:07 -07:00
fs mm/fs: delete PF_SWAPWRITE 2022-03-22 15:57:08 -07:00
include NUMA Balancing: add page promotion counter 2022-03-22 15:57:09 -07:00
init lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() 2022-01-22 08:33:37 +02:00
ipc fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
kernel cma: factor out minimum alignment requirement 2022-03-22 15:57:05 -07:00
lib xarray: use kmem_cache_alloc_lru to allocate xa_node 2022-03-22 15:57:03 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm NUMA Balancing: add page promotion counter 2022-03-22 15:57:09 -07:00
net fs: allocate inode by using alloc_inode_sb() 2022-03-22 15:57:03 -07:00
samples samples/seccomp: Adjust sample to also provide kill option 2022-02-10 19:09:12 -08:00
scripts scripts/spelling.txt: add more spellings to spelling.txt 2022-03-22 15:57:00 -07:00
security selinux/stable-5.17 PR 20220223 2022-02-23 17:19:55 -08:00
sound ALSA: intel_hdmi: Fix reference to PCM buffer address 2022-03-02 09:25:37 +01:00
tools userfaultfd/selftests: fix uninitialized_var.cocci warning 2022-03-22 15:57:08 -07:00
usr kbuild: remove include/linux/cyclades.h from header file check 2022-01-27 08:51:08 +01:00
virt KVM: Fix lockdep false negative during host resume 2022-02-17 09:52:50 -05:00
.clang-format genirq/msi: Make interrupt allocation less convoluted 2021-12-16 22:22:20 +01:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap MAINTAINERS: Update Jisheng's email address 2022-03-08 17:30:32 +01:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: replace a Microchip AT91 maintainer 2022-02-09 11:30:01 +01:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Add Paolo Abeni to networking maintainers 2022-03-15 12:16:10 -07:00
Makefile Linux 5.17 2022-03-20 13:14:17 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.