From: Boris Burkov <boris@bur.io>
To: linux-btrfs@vger.kernel.org, kernel-team@fb.com
Subject: [PATCH 0/2] btrfs: ENOSPC fixes for unused block groups
Date: Tue, 22 Sep 2026 09:55:36 -0700 [thread overview]
Message-ID: <cover.1790095812.git.boris@bur.io> (raw)
A few fixes for system chunk allocation ENOSPCs caused by a sudden influx of a
large number of unused block groups in a filesystem with no free dev extents.
In practice, I saw this on a fully allocated fs with 30TB of space, a 4MiB
system chunk (single metadata mode) and ~10k unused data BGs.
- The first patch tries to avoid the condition by allocating earlier for the
system chunk.
- The second patch eagerly commits a single deletion when the system chunk is
at risk.
More details in the patches themselves.
Boris Burkov (2):
btrfs: allocate additional SYSTEM space earlier
btrfs: commit after deleting an unused block group if system space is
low
fs/btrfs/block-group.c | 43 +++++++++++++++++++++++++++++++++++++++---
1 file changed, 40 insertions(+), 3 deletions(-)
--
2.55.0
next reply other threads:[~2026-09-22 16:55 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-22 16:55 Boris Burkov [this message]
2026-09-22 16:55 ` [PATCH 1/2] btrfs: allocate additional SYSTEM space earlier Boris Burkov
2026-09-28 10:58 ` Filipe Manana
2026-09-28 20:04 ` Boris Burkov
2026-09-22 16:55 ` [PATCH 2/2] btrfs: commit after deleting an unused block group if system space is low Boris Burkov
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