From: Vitaly Wool <vitalywool@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Linux-MM <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>,
Oleksiy.Avramchenko@sony.com, Guenter Roeck <linux@roeck-us.net>
Subject: Re: [PATCH] z3fold: encode object length in the handle
Date: Mon, 29 Oct 2018 13:27:36 +0100 [thread overview]
Message-ID: <CAMJBoFMWV-HbymH6D0PYF6EJFoLoheDHCwaQgZiadvd7BZSE2w@mail.gmail.com> (raw)
In-Reply-To: <20181025124249.0ba63f1041ed8836ff6e6190@linux-foundation.org>
[-- Attachment #1: Type: text/plain, Size: 896 bytes --]
Hi Andrew,
Den tors 25 okt. 2018 kl 21:42 skrev Andrew Morton <
akpm@linux-foundation.org>:
> On Thu, 25 Oct 2018 11:28:21 +0200 Vitaly Wool <vitalywool@gmail.com>
> wrote:
>
> > Reclaim and free can race on an object (which is basically ok) but
> > in order for reclaim to be able to map "freed" object we need to
> > encode object length in the handle. handle_to_chunks() is thus
> > introduced to extract object length from a handle and use it during
> > mapping of the last object we couldn't correctly map before.
>
> What are the runtime effects of this change?
>
I haven't observed any adverse impact with this change used in zswap (and
in fact, this is a bugfix for zswap operation). There is a slight under 1%
impact when z3fold is used with ZRAM but since the support for ZRAM over
zpool is still out of tree, I take it doesn't matter at this point, right?
Best regards,
Vitaly
[-- Attachment #2: Type: text/html, Size: 1346 bytes --]
next prev parent reply other threads:[~2018-10-29 12:27 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-25 9:28 Vitaly Wool
2018-10-25 19:42 ` Andrew Morton
2018-10-29 12:27 ` Vitaly Wool [this message]
2018-11-07 23:00 ` Andrew Morton
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=CAMJBoFMWV-HbymH6D0PYF6EJFoLoheDHCwaQgZiadvd7BZSE2w@mail.gmail.com \
--to=vitalywool@gmail.com \
--cc=Oleksiy.Avramchenko@sony.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux@roeck-us.net \
/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