From: Stefan Priebe - Profihost AG <s.priebe@profihost.ag>
To: "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Subject: high cpu usage due to btrfs_find_space_for_alloc and rb_next
Date: Sat, 18 Feb 2017 08:16:16 +0100 [thread overview]
Message-ID: <02d3d58e-a254-eda5-a18a-36983d1e9f78@profihost.ag> (raw)
Hi,
is there any chance to optimize btrfs_find_space_for_alloc / rb_next on
big devices?
I've plenty of free space but most of the time there's only low I/O but
high cpu usage. perf top shows:
60,41% [kernel] [k] rb_next
9,74% [kernel] [k] btrfs_find_space_for_alloc
5,55% [kernel] [k] tree_search_offset.isra.25
# btrfs filesystem df /backup/
Data, single: total=14.85TiB, used=14.37TiB
System, single: total=32.00MiB, used=2.27MiB
Metadata, single: total=63.00GiB, used=54.87GiB
GlobalReserve, single: total=512.00MiB, used=80.17MiB
--
Stefan
reply other threads:[~2017-02-18 7:21 UTC|newest]
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