All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Mike Christie <michael.christie@oracle.com>
Cc: martin.petersen@oracle.com, linux-scsi@vger.kernel.org,
	target-devel@vger.kernel.org, jasowang@redhat.com,
	stefanha@redhat.com, virtualization@lists.linux-foundation.org
Subject: Re: [PATCH 00/11] target: fix cmd plugging and completion
Date: Mon, 8 Feb 2021 07:01:23 -0500	[thread overview]
Message-ID: <20210208070050-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20210204113513.93204-1-michael.christie@oracle.com>

On Thu, Feb 04, 2021 at 05:35:02AM -0600, Mike Christie wrote:
> The following patches made over Martin's 5.12 branches fix two
> issues:
> 
> 1. target_core_iblock plugs and unplugs the queue for every
> command. To handle this issue and handle an issue that
> vhost-scsi and loop were avoiding by adding their own workqueue,
> I added a new submission workqueue to LIO. Drivers can pass cmds
> to it, and we can then submit batches of cmds.
> 
> 2. vhost-scsi and loop on the submission side were doing a work
> per cmd and on the lio completion side it was doing a work per
> cmd. The cap on running works is 512 (max_active) and so we can
> end up end up using a lot of threads when submissions start blocking
> because they hit the block tag limit or the completion side blocks
> trying to send the cmd. In this patchset I just use a cmd list
> per session to avoid abusing the workueue layer.
> 
> The combined patchset fixes a major perf issue we've been hitting
> where IOPs is stuck at 230K when running:
> 
>     fio --filename=/dev/sda  --direct=1 --rw=randrw --bs=4k
>     --ioengine=libaio --iodepth=128  --numjobs=8 --time_based
>     --group_reporting --runtime=60
> 
> The patches in this set get me to 350K when using devices that
> have native IOPs of around 400-500K.
> 
> Note that 5.12 has some interrupt changes that my patches
> collide with. Martin's 5.12 branches had the changes so I
> based my patches on that.
> 

OK so feel free to merge through that branch.

Acked-by: Michael S. Tsirkin <mst@redhat.com>

-- 
MST


WARNING: multiple messages have this Message-ID (diff)
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Mike Christie <michael.christie@oracle.com>
Cc: martin.petersen@oracle.com, linux-scsi@vger.kernel.org,
	virtualization@lists.linux-foundation.org,
	target-devel@vger.kernel.org, stefanha@redhat.com
Subject: Re: [PATCH 00/11] target: fix cmd plugging and completion
Date: Mon, 8 Feb 2021 07:01:23 -0500	[thread overview]
Message-ID: <20210208070050-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20210204113513.93204-1-michael.christie@oracle.com>

On Thu, Feb 04, 2021 at 05:35:02AM -0600, Mike Christie wrote:
> The following patches made over Martin's 5.12 branches fix two
> issues:
> 
> 1. target_core_iblock plugs and unplugs the queue for every
> command. To handle this issue and handle an issue that
> vhost-scsi and loop were avoiding by adding their own workqueue,
> I added a new submission workqueue to LIO. Drivers can pass cmds
> to it, and we can then submit batches of cmds.
> 
> 2. vhost-scsi and loop on the submission side were doing a work
> per cmd and on the lio completion side it was doing a work per
> cmd. The cap on running works is 512 (max_active) and so we can
> end up end up using a lot of threads when submissions start blocking
> because they hit the block tag limit or the completion side blocks
> trying to send the cmd. In this patchset I just use a cmd list
> per session to avoid abusing the workueue layer.
> 
> The combined patchset fixes a major perf issue we've been hitting
> where IOPs is stuck at 230K when running:
> 
>     fio --filename=/dev/sda  --direct=1 --rw=randrw --bs=4k
>     --ioengine=libaio --iodepth=128  --numjobs=8 --time_based
>     --group_reporting --runtime=60
> 
> The patches in this set get me to 350K when using devices that
> have native IOPs of around 400-500K.
> 
> Note that 5.12 has some interrupt changes that my patches
> collide with. Martin's 5.12 branches had the changes so I
> based my patches on that.
> 

OK so feel free to merge through that branch.

Acked-by: Michael S. Tsirkin <mst@redhat.com>

-- 
MST

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

  parent reply	other threads:[~2021-02-08 12:04 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-04 11:35 [PATCH 00/11] target: fix cmd plugging and completion Mike Christie
2021-02-04 11:35 ` [PATCH 01/11] target: pass in fabric ops to session creation Mike Christie
2021-02-04 11:35 ` [PATCH 02/11] target: add workqueue cmd submission helper Mike Christie
2021-02-04 23:13   ` Chaitanya Kulkarni
2021-02-05  0:43     ` michael.christie
2021-02-05  1:50       ` Chaitanya Kulkarni
2021-02-04 11:35 ` [PATCH 03/11] tcm loop: use blk cmd allocator for se_cmds Mike Christie
2021-02-04 11:35 ` [PATCH 04/11] tcm loop: use lio wq cmd submission helper Mike Christie
2021-02-04 11:35 ` [PATCH 05/11] vhost scsi: " Mike Christie
2021-02-05 16:17   ` Michael S. Tsirkin
2021-02-05 16:17     ` Michael S. Tsirkin
2021-02-05 17:38     ` Mike Christie
2021-02-05 18:04       ` Mike Christie
2021-02-04 11:35 ` [PATCH 06/11] target: cleanup cmd flag bits Mike Christie
2021-02-04 23:15   ` Chaitanya Kulkarni
2021-02-04 11:35 ` [PATCH 07/11] target: fix backend plugging Mike Christie
2021-02-04 11:35 ` [PATCH 08/11] target iblock: add backend plug/unplug callouts Mike Christie
2021-02-04 23:23   ` Chaitanya Kulkarni
2021-02-05  0:45     ` michael.christie
2021-02-07  1:06   ` Chaitanya Kulkarni
2021-02-07  2:21     ` Bart Van Assche
2021-02-07  2:21       ` Bart Van Assche
2021-02-04 11:35 ` [PATCH 09/11] target_core_user: " Mike Christie
2021-02-04 23:25   ` Chaitanya Kulkarni
2021-02-07 21:37     ` Mike Christie
2021-02-04 11:35 ` [PATCH 10/11] target: replace work per cmd in completion path Mike Christie
2021-02-04 23:26   ` Chaitanya Kulkarni
2021-02-04 11:35 ` [PATCH 11/11] target, vhost-scsi: don't switch cpus on completion Mike Christie
2021-02-08 10:48 ` [PATCH 00/11] target: fix cmd plugging and completion Stefan Hajnoczi
2021-02-08 10:48   ` Stefan Hajnoczi
2021-02-08 12:01 ` Michael S. Tsirkin [this message]
2021-02-08 12:01   ` Michael S. Tsirkin

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=20210208070050-mutt-send-email-mst@kernel.org \
    --to=mst@redhat.com \
    --cc=jasowang@redhat.com \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=michael.christie@oracle.com \
    --cc=stefanha@redhat.com \
    --cc=target-devel@vger.kernel.org \
    --cc=virtualization@lists.linux-foundation.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 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.