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Date:   Tue, 4 Apr 2023 23:18:48 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Chris Mason <clm@meta.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Linux regressions mailing list <regressions@lists.linux.dev>,
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        anand.jain@oracle.com, boris@bur.io, clm@fb.com, dsterba@suse.com,
        linux-btrfs@vger.kernel.org
Subject: Re: [6.2 regression][bisected]discard storm on idle since
 v6.1-rc8-59-g63a7cb130718 discard=async
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On Tue, Apr 04, 2023 at 02:15:38PM -0400, Chris Mason wrote:
> It seems like a good time to talk through a variations of discard usage
> in fb data centers.  We run a pretty wide variety of hardware from
> consumer grade ssds to enterprise ssds, and we've run these on
> ext4/btrfs/xfs.

Remember what you guys call consumer grade is the top of the shelve
consumer grade SSDs, or in fact low-end enterprise ones that are based
on the latest and greatest top shelve SSDs with firmware specifically
tweaked for you.  That is a whole differnet level from random crappy
no-name SSD from 5 years ago.