From: Christoph Hellwig <hch@lst.de>
To: kernel test robot <oliver.sang@intel.com>
Cc: Christoph Hellwig <hch@lst.de>,
oe-lkp@lists.linux.dev, lkp@intel.com,
linux-kernel@vger.kernel.org, Carlos Maiolino <cem@kernel.org>,
Carlos Maiolino <cmaiolino@redhat.com>,
"Darrick J. Wong" <djwong@kernel.org>,
linux-xfs@vger.kernel.org
Subject: Re: [linus:master] [xfs] 9b64ca202f: fxmark.ssd_xfs_DRBH_4_bufferedio.works/sec 24.1% regression
Date: Fri, 17 Jul 2026 08:48:07 +0200 [thread overview]
Message-ID: <20260717064807.GA23992@lst.de> (raw)
In-Reply-To: <202607161601.867c143e-lkp@intel.com>
On Thu, Jul 16, 2026 at 09:13:19PM +0800, kernel test robot wrote:
>
>
> Hello,
>
> kernel test robot noticed a 24.1% regression of fxmark.ssd_xfs_DRBH_4_bufferedio.works/sec on:
>
This looks really odd. While the patch adds a bit more computation,
that is very cheap shifting and masking. So the only theory I have here
is that this somehow affects the inode data layout. Can you re-run this
with the patch below applied on top of commit
9b64ca202f364a6bf8e19bdd20953bc2d776c67f ?
diff --git a/fs/xfs/libxfs/xfs_inode_buf.h b/fs/xfs/libxfs/xfs_inode_buf.h
index 57192adc7744..319e83d4a087 100644
--- a/fs/xfs/libxfs/xfs_inode_buf.h
+++ b/fs/xfs/libxfs/xfs_inode_buf.h
@@ -15,6 +15,7 @@ struct xfs_dinode;
*/
struct xfs_imap {
xfs_agblock_t im_agbno; /* starting agbno of inode cluster */
+ uint32_t __im_pad;
unsigned short im_boffset; /* offset in inode cluster in bytes */
};
prev parent reply other threads:[~2026-07-17 6:48 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-16 13:13 [linus:master] [xfs] 9b64ca202f: fxmark.ssd_xfs_DRBH_4_bufferedio.works/sec 24.1% regression kernel test robot
2026-07-17 6:48 ` Christoph Hellwig [this message]
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