From: "santosh.shilimkar@oracle•com" <santosh.shilimkar@oracle•com>
To: Christoph Hellwig <hch@infradead•org>
Cc: netdev@vger•kernel.org, davem@davemloft•net,
linux-kernel@vger•kernel.org
Subject: Re: [net-next][PATCH v2 11/13] RDS: IB: add Fastreg MR (FRMR) detection support
Date: Sun, 28 Feb 2016 02:26:14 -0800 [thread overview]
Message-ID: <56D2CB46.8010904@oracle.com> (raw)
In-Reply-To: <20160228090858.GB6671@infradead.org>
On 2/28/16 1:08 AM, Christoph Hellwig wrote:
> On Sat, Feb 27, 2016 at 06:19:48PM -0800, Santosh Shilimkar wrote:
>> Discovere Fast Memmory Registration support using IB device
>> IB_DEVICE_MEM_MGT_EXTENSIONS. Certain HCA might support just FRMR
>> or FMR or both FMR and FRWR. In case both mr type are supported,
>> default FMR is used.
>>
>> Default MR is still kept as FMR against what everyone else
>> is following. Default will be changed to FRMR once the
>> RDS performance with FRMR is comparable with FMR. The
>> work is in progress for the same.
>>
>> Signed-off-by: Santosh Shilimkar <ssantosh@kernel•org>
>> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle•com>
>> ---
>> v2: Dropped the module parameter as suggested by David Miller
>
> This means we only use the safer method if the HCA doesn't support
> the other one. All other RDMA ULP that support both methods have
> a module_param so the veto from Dave is a bit unfortunate. Anyway,
> let's get the code in for now and figure out what to use later.
>
Indeed. It wasn't really deal breaker for RDS so I agreed to drop it.
> Just curious: where / how do you see worse peformance using FRs?
>
I wouldn't call it worse but its not comparable. Use case
is multi-threaded RDS RDMA perf test(s). Hopefully the follow
up series which am working on should minimise the gap. I am
leaving the details for later, but one of the main issue I
saw was contention on driver post_send() lock from send, MR reg
and MR invalidation.
Regards,
Santosh
next prev parent reply other threads:[~2016-02-28 10:26 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-28 2:19 [net-next][PATCH v2 00/13] RDS: Major clean-up with couple of new features for 4.6 Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 01/13] RDS: Drop stale iWARP RDMA transport Santosh Shilimkar
2016-02-28 9:05 ` Christoph Hellwig
2016-02-28 10:11 ` santosh.shilimkar
2016-02-28 19:51 ` Or Gerlitz
2016-02-29 0:26 ` santosh.shilimkar
2016-03-02 10:54 ` Or Gerlitz
2016-02-28 2:19 ` [net-next][PATCH v2 02/13] RDS: Add support for SO_TIMESTAMP for incoming messages Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 03/13] MAINTAINERS: update RDS entry Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 04/13] RDS: IB: Remove the RDS_IB_SEND_OP dependency Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 05/13] RDS: IB: Re-organise ibmr code Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 06/13] RDS: IB: create struct rds_ib_fmr Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 07/13] RDS: IB: move FMR code to its own file Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 08/13] RDS: IB: add connection info to ibmr Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 09/13] RDS: IB: handle the RDMA CM time wait event Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 10/13] RDS: IB: add mr reused stats Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 11/13] RDS: IB: add Fastreg MR (FRMR) detection support Santosh Shilimkar
2016-02-28 9:08 ` Christoph Hellwig
2016-02-28 10:26 ` santosh.shilimkar [this message]
2016-02-28 2:19 ` [net-next][PATCH v2 12/13] RDS: IB: allocate extra space on queues for FRMR support Santosh Shilimkar
2016-02-28 2:19 ` [net-next][PATCH v2 13/13] RDS: IB: Support Fastreg MR (FRMR) memory registration mode Santosh Shilimkar
2016-03-01 22:33 ` [net-next][PATCH v2 00/13] RDS: Major clean-up with couple of new features for 4.6 David Miller
2016-03-01 23:09 ` santosh shilimkar
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=56D2CB46.8010904@oracle.com \
--to=santosh.shilimkar@oracle$(echo .)com \
--cc=davem@davemloft$(echo .)net \
--cc=hch@infradead$(echo .)org \
--cc=linux-kernel@vger$(echo .)kernel.org \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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