From: Matthew Wilcox <willy@linux.intel.com>
To: Jens Axboe <axboe@fb.com>
Cc: "Keith Busch" <keith.busch@intel.com>,
"Matias Bjørling" <m@bjorling.me>,
"sbradshaw@micron.com" <sbradshaw@micron.com>,
"tom.leiming@gmail.com" <tom.leiming@gmail.com>,
"hch@infradead.org" <hch@infradead.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>
Subject: Re: [PATCH v7] NVMe: conversion to blk-mq
Date: Wed, 11 Jun 2014 13:09:17 -0400 [thread overview]
Message-ID: <20140611170917.GA12025@linux.intel.com> (raw)
In-Reply-To: <539889DC.7090704@fb.com>
On Wed, Jun 11, 2014 at 10:54:52AM -0600, Jens Axboe wrote:
> OK, so essentially any single request must be a virtually contig piece
> of memory. Is there any size limitations to how big this contig segment
> can be?
The maximum size of an I/O is 65536 sectors. So on a 512-byte sector
device, that's 32MB, but on a 4k sector size device, that's 128MB.
> I think this is unique requirement, at least I haven't seen other pieces
> of hardware have it. But it would be pretty trivial to add a setting to
> limit merges based on virtually contig, similarly to what is done for
> number of physical segments.
I think there might be an FCoE device with that requirement too.
next prev parent reply other threads:[~2014-06-11 17:09 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-10 9:20 [PATCH v7] conversion to blk-mq Matias Bjørling
2014-06-10 9:20 ` [PATCH v7] NVMe: " Matias Bjørling
2014-06-10 15:51 ` Keith Busch
2014-06-10 16:19 ` Jens Axboe
2014-06-10 19:29 ` Keith Busch
2014-06-10 19:58 ` Jens Axboe
2014-06-10 21:10 ` Keith Busch
2014-06-10 21:14 ` Jens Axboe
2014-06-10 21:21 ` Keith Busch
2014-06-10 21:33 ` Matthew Wilcox
2014-06-11 16:54 ` Jens Axboe
2014-06-11 17:09 ` Matthew Wilcox [this message]
2014-06-11 22:22 ` Matias Bjørling
2014-06-11 22:51 ` Keith Busch
2014-06-12 14:32 ` Matias Bjørling
2014-06-12 16:24 ` Keith Busch
2014-06-13 0:06 ` Keith Busch
2014-06-13 14:07 ` Jens Axboe
2014-06-13 15:05 ` Keith Busch
2014-06-13 15:11 ` Jens Axboe
2014-06-13 15:16 ` Keith Busch
2014-06-13 18:14 ` Jens Axboe
2014-06-13 19:22 ` Keith Busch
2014-06-13 19:29 ` Jens Axboe
2014-06-13 20:56 ` Jens Axboe
2014-06-13 21:28 ` Jens Axboe
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=20140611170917.GA12025@linux.intel.com \
--to=willy@linux.intel.com \
--cc=axboe@fb.com \
--cc=hch@infradead.org \
--cc=keith.busch@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=m@bjorling.me \
--cc=sbradshaw@micron.com \
--cc=tom.leiming@gmail.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox