From: Roman Gushchin <guro@fb.com>
To: "Tobin C. Harding" <tobin@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Matthew Wilcox <willy@infradead.org>,
Alexander Viro <viro@ftp.linux.org.uk>,
"Christoph Hellwig" <hch@infradead.org>,
Pekka Enberg <penberg@cs.helsinki.fi>,
"David Rientjes" <rientjes@google.com>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
Christopher Lameter <cl@linux.com>,
Miklos Szeredi <mszeredi@redhat.com>,
Andreas Dilger <adilger@dilger.ca>,
Waiman Long <longman@redhat.com>,
"Tycho Andersen" <tycho@tycho.ws>, Theodore Ts'o <tytso@mit.edu>,
Andi Kleen <ak@linux.intel.com>,
David Chinner <david@fromorbit.com>,
Nick Piggin <npiggin@gmail.com>, Rik van Riel <riel@redhat.com>,
Hugh Dickins <hughd@google.com>, Jonathan Corbet <corbet@lwn.net>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH v5 13/16] slub: Enable balancing slabs across nodes
Date: Tue, 21 May 2019 01:04:10 +0000 [thread overview]
Message-ID: <20190521010404.GB9552@tower.DHCP.thefacebook.com> (raw)
In-Reply-To: <20190520054017.32299-14-tobin@kernel.org>
On Mon, May 20, 2019 at 03:40:14PM +1000, Tobin C. Harding wrote:
> We have just implemented Slab Movable Objects (SMO). On NUMA systems
> slabs can become unbalanced i.e. many slabs on one node while other
> nodes have few slabs. Using SMO we can balance the slabs across all
> the nodes.
>
> The algorithm used is as follows:
>
> 1. Move all objects to node 0 (this has the effect of defragmenting the
> cache).
This already sounds dangerous (or costly). Can't it be done without
cross-node data moves?
>
> 2. Calculate the desired number of slabs for each node (this is done
> using the approximation nr_slabs / nr_nodes).
So that on this step only (actual data size - desired data size) has
to be moved?
Thanks!
next prev parent reply other threads:[~2019-05-21 1:04 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-20 5:40 [RFC PATCH v5 00/16] Slab Movable Objects (SMO) Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 01/16] slub: Add isolate() and migrate() methods Tobin C. Harding
2019-05-21 0:37 ` Roman Gushchin
2019-05-20 5:40 ` [RFC PATCH v5 02/16] tools/vm/slabinfo: Add support for -C and -M options Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 03/16] slub: Sort slab cache list Tobin C. Harding
2019-05-21 0:38 ` Roman Gushchin
2019-05-20 5:40 ` [RFC PATCH v5 04/16] slub: Slab defrag core Tobin C. Harding
2019-05-21 0:51 ` Roman Gushchin
2019-05-21 1:15 ` Tobin C. Harding
2019-05-21 1:25 ` Roman Gushchin
2019-05-20 5:40 ` [RFC PATCH v5 05/16] tools/vm/slabinfo: Add remote node defrag ratio output Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 06/16] tools/vm/slabinfo: Add defrag_used_ratio output Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 07/16] tools/testing/slab: Add object migration test module Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 08/16] tools/testing/slab: Add object migration test suite Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 09/16] lib: Separate radix_tree_node and xa_node slab cache Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 10/16] xarray: Implement migration function for xa_node objects Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 11/16] tools/testing/slab: Add XArray movable objects tests Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 12/16] slub: Enable moving objects to/from specific nodes Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 13/16] slub: Enable balancing slabs across nodes Tobin C. Harding
2019-05-21 1:04 ` Roman Gushchin [this message]
2019-05-21 1:44 ` Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 14/16] dcache: Provide a dentry constructor Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 15/16] dcache: Implement partial shrink via Slab Movable Objects Tobin C. Harding
2019-05-20 5:40 ` [RFC PATCH v5 16/16] dcache: Add CONFIG_DCACHE_SMO Tobin C. Harding
2019-05-21 0:57 ` Roman Gushchin
2019-05-21 1:31 ` Tobin C. Harding
2019-05-21 2:05 ` Roman Gushchin
2019-05-21 3:15 ` Tobin C. Harding
2019-05-29 3:54 ` Tobin C. Harding
2019-05-29 16:16 ` Roman Gushchin
2019-06-03 4:26 ` Tobin C. Harding
2019-06-03 20:34 ` Roman Gushchin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190521010404.GB9552@tower.DHCP.thefacebook.com \
--to=guro@fb.com \
--cc=adilger@dilger.ca \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=cl@linux.com \
--cc=corbet@lwn.net \
--cc=david@fromorbit.com \
--cc=hch@infradead.org \
--cc=hughd@google.com \
--cc=iamjoonsoo.kim@lge.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=longman@redhat.com \
--cc=mszeredi@redhat.com \
--cc=npiggin@gmail.com \
--cc=penberg@cs.helsinki.fi \
--cc=riel@redhat.com \
--cc=rientjes@google.com \
--cc=tobin@kernel.org \
--cc=tycho@tycho.ws \
--cc=tytso@mit.edu \
--cc=viro@ftp.linux.org.uk \
--cc=willy@infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).