From: Christoph Hellwig <hch@lst.de>
To: Amir Goldstein <amir73il@gmail.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>,
Dave Chinner <david@fromorbit.com>,
linux-xfs <linux-xfs@vger.kernel.org>,
Christoph Hellwig <hch@lst.de>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [QUESTION] Long read latencies on mixed rw buffered IO
Date: Mon, 25 Mar 2019 19:02:13 +0100 [thread overview]
Message-ID: <20190325180213.GA31766@lst.de> (raw)
In-Reply-To: <CAOQ4uxjh2w3PeyftwJS5djndVp0kSRwf9ki1FUMRqCU9H+uDTg@mail.gmail.com>
On Mon, Mar 25, 2019 at 07:56:33PM +0200, Amir Goldstein wrote:
> Sure, let's give that a shot. But allow me to stay skeptical, because
> I don't think there is a one-size-fits-all solution.
> If application doesn't need >4K atomicity and xfs imposes file-wide
> read locks, there is bound to exist a workload where ext4 can guaranty
> lower latencies than xfs.
>
> Then again, if we fix rw_semaphore to do a good enough job for my
> workload, I may not care about those worst case workloads...
Downgrading these long standing guarantees is simply not an option.
Not quite sure what the I/O pattern of your workload is, but if it
is reads from other regions than you write to you should look into
implementing range locks.
next prev parent reply other threads:[~2019-03-25 18:02 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-24 18:18 [QUESTION] Long read latencies on mixed rw buffered IO Amir Goldstein
2019-03-25 0:10 ` Dave Chinner
2019-03-25 6:51 ` Christoph Hellwig
2019-03-25 6:55 ` Amir Goldstein
2019-03-25 7:49 ` Amir Goldstein
2019-03-25 15:47 ` Darrick J. Wong
2019-03-25 16:41 ` Matthew Wilcox
2019-03-25 17:30 ` Amir Goldstein
2019-03-25 18:22 ` Matthew Wilcox
2019-03-25 19:18 ` Amir Goldstein
2019-03-25 19:40 ` Matthew Wilcox
2019-03-25 19:57 ` Amir Goldstein
2019-03-25 23:48 ` Dave Chinner
2019-03-26 3:44 ` Amir Goldstein
2019-03-27 1:29 ` Dave Chinner
2019-03-25 17:56 ` Amir Goldstein
2019-03-25 18:02 ` Christoph Hellwig [this message]
2019-03-25 18:44 ` Amir Goldstein
2019-03-25 23:43 ` Dave Chinner
2019-03-26 4:36 ` Amir Goldstein
2025-06-20 13:46 ` [PATCH] xfs: Remove i_rwsem lock in buffered read Jinliang Zheng
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