From: Bart Van Assche <bart.vanassche-XdAiOPVOjttBDgjK7y7TUQ@public.gmane.org>
To: Christoph Hellwig <hch-jcswGhMUV9g@public.gmane.org>
Cc: "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
"linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Subject: Re: [PATCH 2/2] IB/iser: set max_segment_size
Date: Tue, 12 Apr 2016 11:13:52 -0700 [thread overview]
Message-ID: <570D3AE0.4040104@sandisk.com> (raw)
In-Reply-To: <20160412165130.GB9568-jcswGhMUV9g@public.gmane.org>
On 04/12/2016 09:51 AM, Christoph Hellwig wrote:
> On Tue, Apr 12, 2016 at 08:34:03AM -0700, Bart Van Assche wrote:
>> ib_sg_to_pages() can handle segments that are larger than mr->page_size.
>
> The interface handles it fine, but we'll still end up using a segment
> per (MR) page.
>
>> Have you considered to set queue_limits.max_hw_sectors instead of
>> max_segment_size?
>
> That's what NVMe does, but I don't think it's a good idea. Because
> of the unaligned start into the page this means you have to set the limit
> to one lower than the actual hardware limit.
I think this means that there is a mismatch between the current block
layer limits and what NVMe / RDMA drivers need ...
Bart.
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2016-04-12 18:13 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-12 14:13 fix large I/O regression with iSER in 4.4+ V2 Christoph Hellwig
[not found] ` <1460470405-11673-1-git-send-email-hch-jcswGhMUV9g@public.gmane.org>
2016-04-12 14:13 ` [PATCH 1/2] scsi: add a max_segment_size limitation to struct Scsi_Host Christoph Hellwig
2016-04-12 15:19 ` Bart Van Assche
2016-04-12 15:37 ` Laurence Oberman
[not found] ` <1460470405-11673-2-git-send-email-hch-jcswGhMUV9g@public.gmane.org>
2016-04-13 9:39 ` Sagi Grimberg
2016-04-12 14:13 ` [PATCH 2/2] IB/iser: set max_segment_size Christoph Hellwig
2016-04-12 15:34 ` Bart Van Assche
2016-04-12 16:51 ` Christoph Hellwig
[not found] ` <20160412165130.GB9568-jcswGhMUV9g@public.gmane.org>
2016-04-12 18:13 ` Bart Van Assche [this message]
[not found] ` <570D3AE0.4040104-XdAiOPVOjttBDgjK7y7TUQ@public.gmane.org>
2016-04-12 18:43 ` Christoph Hellwig
[not found] ` <20160412184309.GA3333-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2016-04-13 14:07 ` Christoph Hellwig
2016-04-13 9:39 ` Sagi Grimberg
[not found] ` <1460470405-11673-3-git-send-email-hch-jcswGhMUV9g@public.gmane.org>
2016-04-28 7:40 ` Or Gerlitz
-- strict thread matches above, loose matches on Subject: below --
2016-04-11 22:47 fix large I/O regression with iSER in 4.4+ Christoph Hellwig
2016-04-11 22:47 ` [PATCH 2/2] IB/iser: set max_segment_size Christoph Hellwig
2016-04-12 10:48 ` Sagi Grimberg
[not found] ` <570CD26E.70502-NQWnxTmZq1alnMjI0IkVqw@public.gmane.org>
2016-04-12 14:27 ` James Bottomley
[not found] ` <1460471256.2338.5.camel-d9PhHud1JfjCXq6kfMZ53/egYHeGw8Jk@public.gmane.org>
2016-04-12 15:27 ` Christoph Hellwig
2016-04-13 8:01 ` Sagi Grimberg
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=570D3AE0.4040104@sandisk.com \
--to=bart.vanassche-xdaiopvojttbdgjk7y7tuq@public.gmane.org \
--cc=hch-jcswGhMUV9g@public.gmane.org \
--cc=linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.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.