From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: Ritesh Harjani <riteshh@linux.ibm.com>
Cc: linux-ext4@vger.kernel.org, jack@suse.cz,
dan.j.williams@intel.com, anju@linux.vnet.ibm.com,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCHv3 1/1] ext4: Optimize file overwrites
Date: Sat, 3 Oct 2020 00:49:05 -0400 [thread overview]
Message-ID: <20201003044905.GF23474@mit.edu> (raw)
In-Reply-To: <88e795d8a4d5cd22165c7ebe857ba91d68d8813e.1600401668.git.riteshh@linux.ibm.com>
On Fri, Sep 18, 2020 at 10:36:35AM +0530, Ritesh Harjani wrote:
> In case if the file already has underlying blocks/extents allocated
> then we don't need to start a journal txn and can directly return
> the underlying mapping. Currently ext4_iomap_begin() is used by
> both DAX & DIO path. We can check if the write request is an
> overwrite & then directly return the mapping information.
>
> This could give a significant perf boost for multi-threaded writes
> specially random overwrites.
> On PPC64 VM with simulated pmem(DAX) device, ~10x perf improvement
> could be seen in random writes (overwrite). Also bcoz this optimizes
> away the spinlock contention during jbd2 slab cache allocation
> (jbd2_journal_handle). On x86 VM, ~2x perf improvement was observed.
>
> Reported-by: Dan Williams <dan.j.williams@intel.com>
> Suggested-by: Jan Kara <jack@suse.cz>
> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Thanks, applied.
- Ted
prev parent reply other threads:[~2020-10-03 4:49 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-18 5:06 [PATCHv3 0/1] Optimize ext4 file overwrites - perf improvement Ritesh Harjani
2020-09-18 5:06 ` [PATCHv3 1/1] ext4: Optimize file overwrites Ritesh Harjani
2020-09-18 7:52 ` Sedat Dilek
2020-09-18 9:52 ` Jan Kara
2020-09-25 7:12 ` [ext4] 4e8fc10115: fio.write_iops 330.6% improvement kernel test robot
2020-09-25 7:12 ` kernel test robot
2020-10-03 4:49 ` Theodore Y. Ts'o [this message]
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=20201003044905.GF23474@mit.edu \
--to=tytso@mit.edu \
--cc=anju@linux.vnet.ibm.com \
--cc=dan.j.williams@intel.com \
--cc=jack@suse.cz \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=riteshh@linux.ibm.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.