Re: Regression in v5.14-rc1: f2165627319f btrfs: compression: don't try to compress if we don't have enough pages
From: David Sterba <hidden>
Date: 2021-08-23 11:20:21
On Sun, Aug 22, 2021 at 01:51:15AM -0400, Zygo Blaxell wrote:
Before this commit: # head /dev/zero -c 4095 > inline # compsize inline Type Perc Disk Usage Uncompressed Referenced TOTAL 0% 18B 3.9K 3.9K zstd 0% 18B 3.9K 3.9K After this commit: # head /dev/zero -c 4095 > inline # compsize inline Processed 1 file, 1 regular extents (1 refs), 0 inline. Type Perc Disk Usage Uncompressed Referenced TOTAL 100% 4.0K 4.0K 4.0K none 100% 4.0K 4.0K 4.0K This change makes the metadata sizes of trees of small files (e.g. source checkouts) blow up. It looks like we need to look at the offset of the extent, as well as its length.
Thanks for the report, my bad, I'll look into it.