From: Josef Bacik <josef@toxicpanda.com>
To: Anand Jain <anand.jain@oracle.com>, linux-btrfs@vger.kernel.org
Cc: dsterba@suse.com
Subject: Re: [PATCH RFC 4/4] btrfs: introduce new read_policy round-robin
Date: Tue, 19 Jan 2021 14:41:34 -0500 [thread overview]
Message-ID: <b0cf6a1d-bd50-dbd5-ff8e-d24ab547e57a@toxicpanda.com> (raw)
In-Reply-To: <8e0afaa33f33d1a5efbf37fa4465954056ce3f59.1610324448.git.anand.jain@oracle.com>
On 1/11/21 4:41 AM, Anand Jain wrote:
> Add round-robin read policy to route the read IO to the next device in the
> round-robin order. The chunk allocation and thus the stripe-index follows
> the order of free space available on devices. So to make the round-robin
> effective it shall follow the devid order instead of the stripe-index
> order.
>
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> --
> RFC because: Provides terrible performance with the fio tests.
> I am not yet sure if there is any io workload or a block layer
> tuning that shall make this policy better. As of now just an
> experimental patch.
>
Just drop this one, if we can't find a reason to use it then don't bother adding
the code. The other options have real world valuable uses, so stick with those.
Thanks,
Josef
next prev parent reply other threads:[~2021-01-19 19:43 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-11 9:41 [PATCH v3 0/4] btrfs: read_policy types latency, device and round-robin Anand Jain
2021-01-11 9:41 ` [PATCH v3 1/4] btrfs: add read_policy latency Anand Jain
2021-01-19 19:36 ` Josef Bacik
2021-01-20 2:43 ` Anand Jain
2021-01-20 10:27 ` Michal Rostecki
2021-01-20 12:30 ` Anand Jain
2021-01-20 13:54 ` Michal Rostecki
2021-01-21 10:45 ` Anand Jain
2021-01-11 9:41 ` [PATCH v3 2/4] btrfs: introduce new device-state read_preferred Anand Jain
2021-01-19 19:44 ` Josef Bacik
2021-01-11 9:41 ` [PATCH v3 3/4] btrfs: introduce new read_policy device Anand Jain
2021-01-19 19:44 ` Josef Bacik
2021-01-11 9:41 ` [PATCH RFC 4/4] btrfs: introduce new read_policy round-robin Anand Jain
2021-01-19 19:41 ` Josef Bacik [this message]
2021-01-20 2:40 ` Anand Jain
-- strict thread matches above, loose matches on Subject: below --
2020-10-29 7:54 [PATCH v2 0/4] btrfs: read_policy types latency, device and round-robin Anand Jain
2020-10-29 7:54 ` [PATCH RFC 4/4] btrfs: introduce new read_policy round-robin Anand Jain
2020-10-28 13:25 [PATCH v1 0/4] btrfs: read_policy types latency, device and round-robin Anand Jain
2020-10-28 13:26 ` [PATCH RFC 4/4] btrfs: introduce new read_policy round-robin Anand Jain
2020-10-28 14:44 ` Josef Bacik
2020-10-29 2:06 ` Anand Jain
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=b0cf6a1d-bd50-dbd5-ff8e-d24ab547e57a@toxicpanda.com \
--to=josef@toxicpanda.com \
--cc=anand.jain@oracle.com \
--cc=dsterba@suse.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;
as well as URLs for NNTP newsgroup(s).