From: keith.busch@intel.com (Keith Busch)
Subject: [PATCH V3] nvme-pci: add sgl support
Date: Thu, 10 Aug 2017 12:47:23 -0400 [thread overview]
Message-ID: <20170810164722.GD14634@localhost.localdomain> (raw)
In-Reply-To: <20170810085905.GA12494@infradead.org>
On Thu, Aug 10, 2017@01:59:05AM -0700, Christoph Hellwig wrote:
> On Tue, Aug 01, 2017@04:48:04AM -0400, Keith Busch wrote:
> > On Tue, Aug 01, 2017@08:29:00AM +0000, Chaitanya Kulkarni wrote:
> > > [CK] Yes, I've observed approximately %5 better
> > > performance for IO sizes larger than 32k (for sgl_threshold = 32k).
> >
> > Is that a physically contiguous 32k, or does each 4k require a different
> > SG element? Could you try to force both conditions and see how each
> > scenario compares with PRP?
>
> How do we find out the segment alignment without walking the list of
> biovecs, which would be rather annoying.
The biovecs already gets walked and iod->nents will tell you how many
physical segments there are.
prev parent reply other threads:[~2017-08-10 16:47 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-07-26 18:19 [PATCH V3] nvme-pci: add sgl support Chaitanya Kulkarni
2017-07-26 18:19 ` Chaitanya Kulkarni
2017-07-31 6:30 ` Sagi Grimberg
2017-07-31 6:45 ` Sagi Grimberg
2017-07-31 7:13 ` Keith Busch
2017-07-31 11:18 ` Sagi Grimberg
2017-08-01 8:29 ` Chaitanya Kulkarni
2017-08-01 8:48 ` Keith Busch
2017-08-10 8:59 ` Christoph Hellwig
2017-08-10 16:47 ` Keith Busch [this message]
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=20170810164722.GD14634@localhost.localdomain \
--to=keith.busch@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.