From: willy@linux.intel.com (Matthew Wilcox)
Subject: [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@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.
WARNING: multiple messages have this Message-ID (diff)
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: 52+ 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 ` Matias Bjørling
2014-06-10 9:20 ` [PATCH v7] NVMe: " Matias Bjørling
2014-06-10 9:20 ` Matias Bjørling
2014-06-10 15:51 ` Keith Busch
2014-06-10 15:51 ` Keith Busch
2014-06-10 16:19 ` Jens Axboe
2014-06-10 16:19 ` Jens Axboe
2014-06-10 19:29 ` Keith Busch
2014-06-10 19:29 ` Keith Busch
2014-06-10 19:58 ` Jens Axboe
2014-06-10 19:58 ` Jens Axboe
2014-06-10 21:10 ` Keith Busch
2014-06-10 21:10 ` Keith Busch
2014-06-10 21:14 ` Jens Axboe
2014-06-10 21:14 ` Jens Axboe
2014-06-10 21:21 ` Keith Busch
2014-06-10 21:21 ` Keith Busch
2014-06-10 21:33 ` Matthew Wilcox
2014-06-10 21:33 ` Matthew Wilcox
2014-06-11 16:54 ` Jens Axboe
2014-06-11 16:54 ` Jens Axboe
2014-06-11 17:09 ` Matthew Wilcox [this message]
2014-06-11 17:09 ` Matthew Wilcox
2014-06-11 22:22 ` Matias Bjørling
2014-06-11 22:22 ` Matias Bjørling
2014-06-11 22:51 ` Keith Busch
2014-06-11 22:51 ` Keith Busch
2014-06-12 14:32 ` Matias Bjørling
2014-06-12 14:32 ` Matias Bjørling
2014-06-12 16:24 ` Keith Busch
2014-06-12 16:24 ` Keith Busch
2014-06-13 0:06 ` Keith Busch
2014-06-13 0:06 ` Keith Busch
2014-06-13 14:07 ` Jens Axboe
2014-06-13 14:07 ` Jens Axboe
2014-06-13 15:05 ` Keith Busch
2014-06-13 15:05 ` Keith Busch
2014-06-13 15:11 ` Jens Axboe
2014-06-13 15:11 ` Jens Axboe
2014-06-13 15:16 ` Keith Busch
2014-06-13 15:16 ` Keith Busch
2014-06-13 18:14 ` Jens Axboe
2014-06-13 18:14 ` Jens Axboe
2014-06-13 19:22 ` Keith Busch
2014-06-13 19:22 ` Keith Busch
2014-06-13 19:29 ` Jens Axboe
2014-06-13 19:29 ` Jens Axboe
2014-06-13 20:56 ` Jens Axboe
2014-06-13 20:56 ` Jens Axboe
2014-06-13 21:28 ` 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 \
/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.