Linux Btrfs filesystem development
 help / color / mirror / Atom feed
From: David Sterba <dsterba@suse.cz>
To: Anand Jain <anand.jain@oracle.com>
Cc: linux-btrfs@vger.kernel.org
Subject: Re: [PATCH v2 1/9] btrfs: reduce struct btrfs_fs_devices size relocate fsid_change
Date: Wed, 24 May 2023 22:05:00 +0200	[thread overview]
Message-ID: <20230524200500.GC30909@twin.jikos.cz> (raw)
In-Reply-To: <7587a86c31528295d77a707f5c1d795eaec4fe06.1684928629.git.anand.jain@oracle.com>

On Wed, May 24, 2023 at 08:02:35PM +0800, Anand Jain wrote:
> Pack bool fsid_change and bool seeding with other bool declarations in the
> struct btrfs_fs_devices, approximately 6 bytes is saved.
> 
>    before: 512 bytes
>    after: 496 bytes

I checked the difference on a release build and it's even better, 16
bytes, depends on the optional config features in some of the embedded
structures.

--- pre/btrfs.ko.pahole 2023-05-24 21:54:47.326166521 +0200
+++ post/btrfs.ko.pahole        2023-05-24 21:54:47.754166522 +0200
@@ -1700,49 +1700,39 @@ struct btrfs_free_space_op {
...
 
-       /* size: 344, cachelines: 6, members: 27 */
-       /* sum members: 328, holes: 3, sum holes: 16 */
-       /* last cacheline: 24 bytes */
+       /* size: 328, cachelines: 6, members: 27 */
+       /* last cacheline: 8 bytes */

  reply	other threads:[~2023-05-24 20:11 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-24 12:02 [PATCH v2 0/9] btrfs: metadata_uuid refactors part1 Anand Jain
2023-05-24 12:02 ` [PATCH v2 1/9] btrfs: reduce struct btrfs_fs_devices size relocate fsid_change Anand Jain
2023-05-24 20:05   ` David Sterba [this message]
2023-05-24 12:02 ` [PATCH v2 2/9] btrfs: streamline fsid checks in alloc_fs_devices Anand Jain
2023-05-24 12:02 ` [PATCH v2 3/9] btrfs: localise has_metadata_uuid check in alloc_fs_devices args Anand Jain
2023-05-24 12:02 ` [PATCH v2 4/9] btrfs: add comment about metadata_uuid in btrfs_fs_devices Anand Jain
2023-05-24 12:02 ` [PATCH v2 5/9] btrfs: simplify check_tree_block_fsid return arg to bool Anand Jain
2023-05-24 12:02 ` [PATCH v2 6/9] btrfs: refactor with match_fsid_fs_devices helper Anand Jain
2023-05-24 20:56   ` David Sterba
2023-05-24 12:02 ` [PATCH v2 7/9] btrfs: refactor with match_fsid_changed helper Anand Jain
2023-05-24 20:56   ` David Sterba
2023-05-24 12:02 ` [PATCH v2 8/9] btrfs: consolidate uuid memcmp in btrfs_validate_super Anand Jain
2023-05-24 12:02 ` [PATCH v2 9/9] btrfs: add and fix comments in btrfs_fs_devices Anand Jain
2023-05-24 20:57 ` [PATCH v2 0/9] btrfs: metadata_uuid refactors part1 David Sterba
2023-06-27 14:55 ` Guilherme G. Piccoli
2023-06-28  3:52   ` Anand Jain
2023-06-28 13:07     ` Guilherme G. Piccoli

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=20230524200500.GC30909@twin.jikos.cz \
    --to=dsterba@suse.cz \
    --cc=anand.jain@oracle.com \
    --cc=linux-btrfs@vger.kernel.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