From: Martin Wilck <martin.wilck@suse.com>
To: "ming.lei@redhat.com" <ming.lei@redhat.com>,
"axboe@kernel.dk" <axboe@kernel.dk>
Cc: "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>
Subject: Re: [PATCH V2] lib/sbitmap: kill 'depth' from sbitmap_word
Date: Tue, 8 Feb 2022 07:46:03 +0000 [thread overview]
Message-ID: <0f28be75075d260651b215fa435a40152feef93f.camel@suse.com> (raw)
In-Reply-To: <20220110072945.347535-1-ming.lei@redhat.com>
On Mon, 2022-01-10 at 15:29 +0800, Ming Lei wrote:
> Only the last sbitmap_word can have different depth, and all the
> others
> must have same depth of 1U << sb->shift, so not necessary to store it
> in
> sbitmap_word, and it can be retrieved easily and efficiently by
> adding
> one internal helper of __map_depth(sb, index).
>
> Remove 'depth' field from sbitmap_word, then the annotation of
> ____cacheline_aligned_in_smp for 'word' isn't needed any more.
>
> Not see performance effect when running high parallel IOPS test on
> null_blk.
>
> This way saves us one cacheline(usually 64 words) per each
> sbitmap_word.
>
> Cc: Martin Wilck <martin.wilck@suse.com>
> Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Martin Wilck <mwilck@suse.com>
next prev parent reply other threads:[~2022-02-08 7:47 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-01-10 7:29 [PATCH V2] lib/sbitmap: kill 'depth' from sbitmap_word Ming Lei
2022-02-08 3:23 ` Ming Lei
2022-02-08 7:46 ` Martin Wilck [this message]
2022-02-08 9:02 ` John Garry
2022-02-08 13:54 ` Jens Axboe
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=0f28be75075d260651b215fa435a40152feef93f.camel@suse.com \
--to=martin.wilck@suse.com \
--cc=axboe@kernel.dk \
--cc=linux-block@vger.kernel.org \
--cc=ming.lei@redhat.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.