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Date:   Mon, 6 Jan 2020 17:30:01 +0100
From:   David Sterba <dsterba@suse.cz>
To:     Dennis Zhou <dennis@kernel.org>
Cc:     David Sterba <dsterba@suse.com>, Chris Mason <clm@fb.com>,
        Josef Bacik <josef@toxicpanda.com>,
        Omar Sandoval <osandov@osandov.com>, kernel-team@fb.com,
        linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 00/12] btrfs: async discard follow up
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Is it expected to leave the counters in a state where are discardable
extents but not process after a long period of time? I found

discard_bitmap_bytes:316833792
discard_bytes_saved:59390722048
discard_extent_bytes:26122764288
discardable_bytes:44863488
discardable_extents:883
iops_limit:10
kbps_limit:0
max_discard_size:67108864

there was activity when the number of extents wen from about 2000 to
that value (833), so this could bea nother instance of the -1 accounting
bug.