linux-kernel - [PATCH 0/2] Improve the tmpfs large folio read performance

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <cover.1729072803.git.baolin.wang@linux.alibaba.com>
Date: Wed, 16 Oct 2024 18:09:28 +0800
From: Baolin Wang <baolin.wang@...ux.alibaba.com>
To: akpm@...ux-foundation.org,
	hughd@...gle.com
Cc: willy@...radead.org,
	david@...hat.com,
	baolin.wang@...ux.alibaba.com,
	linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 0/2] Improve the tmpfs large folio read performance

The tmpfs has already supported the PMD-sized large folios, but the tmpfs
read operation still performs copying at the PAGE SIZE granularity, which
is not perfect. This patch changes to copy data at the folio granularity,
which can improve the read performance.

Use 'fio bs=64k' to read a 1G tmpfs file populated with 2M THPs, and I can
see about 20% performance improvement, and no regression with bs=4k. I
also did some functional test with the xfstests suite, and I did not find
any regressions with the following xfstests config.
  FSTYP=tmpfs
  export TEST_DIR=/mnt/tempfs_mnt
  export TEST_DEV=/mnt/tempfs_mnt
  export SCRATCH_MNT=/mnt/scratchdir
  export SCRATCH_DEV=/mnt/scratchdir

Baolin Wang (2):
  mm: shmem: update iocb->ki_pos directly to simplify tmpfs read logic
  mm: shmem: improve the tmpfs large folio read performance

 mm/shmem.c | 54 ++++++++++++++++++++++--------------------------------
 1 file changed, 22 insertions(+), 32 deletions(-)

-- 
2.39.3