From: hch@infradead.org (Christoph Hellwig)
Subject: [PATCH] nvme: remove cq check after submission
Date: Wed, 16 May 2018 23:50:49 -0700 [thread overview]
Message-ID: <20180517065049.GA30079@infradead.org> (raw)
In-Reply-To: <20180516212010.GC20223@localhost.localdomain>
On Wed, May 16, 2018@03:20:10PM -0600, Keith Busch wrote:
> On Wed, May 16, 2018@01:58:08PM -0600, Jens Axboe wrote:
> > We always check the completion queue after submitting, but in my testing
> > this isn't a win even on DRAM/xpoint devices. In some cases it's
> > actually worse. Kill it.
>
> Right, this was on my todo list. Agreed it's not helping anything.
> Applied to nvme-4.18.
While I agree in general didn't we have a case where this caused a
regression last time it came up? Not that I'd complain if it goes
away..
But more importantly we could split q_lock into a sq_lock and cq_lock
now, which might bring real benefits.
next prev parent reply other threads:[~2018-05-17 6:50 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-16 19:58 [PATCH] nvme: remove cq check after submission Jens Axboe
2018-05-16 21:20 ` Keith Busch
2018-05-17 6:50 ` Christoph Hellwig [this message]
2018-05-17 14:16 ` Jens Axboe
2018-05-17 15:06 ` Keith Busch
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