Hi Simon,
On Thu, 1 Jun 2023 at 14:10, Jonathan Liu net147@gmail.com wrote:
On Thu, 1 Jun 2023 at 11:27, Jonathan Liu net147@gmail.com wrote:
On Thu, 1 Jun 2023 at 03:13, Simon Glass sjg@chromium.org wrote:
On Wed, 31 May 2023 at 06:52, Jonathan Liu net147@gmail.com wrote:
Hi All,
I noticed that loading from squashfs with zstd compression is significantly slower than ext4 on RK3399 using U-Boot 2022.01. The filesystem is located on eMMC.
I have CONFIG_BLOCK_CACHE=y in .config and am using the generic load command.
ext4: 15682578 bytes read in 366 ms (40.9 MiB/s)
SquashFS with zstd compression: 15685001 bytes read in 2339 ms (6.4 MiB/s)
Any suggestions on how to speed up loading from SquashFS with zstd compression?
Could it just be that zstd is slow? Have you tried lz4?
I tried LZ4 but get "Error: unknown compression type." It seems the SquashFS decompressor only supports lzo, gzip and zstd - https://source.denx.de/u-boot/u-boot/-/blob/master/fs/squashfs/sqfs_decompre...
ext4: 15682578 bytes read in 366 ms (40.9 MiB/s)
SquashFS with lzo compression (~129 MiB squashfs): 15686657 bytes read in 1032 ms (14.5 MiB/s)
SquashFS with gzip compression (~116 MiB squashfs): 15686657 bytes read in 1494 ms (10 MiB/s)
SquashFS with zstd compression (~107 MiB squashfs): 15685001 bytes read in 2339 ms (6.4 MiB/s)
SquashFS with zstd compression seems to be even slower after zstd was updated to 1.5.2 in U-Boot.
SquashFS with zstd compression (~107 MiB squashfs), with zstd 1.5.2 update cherry-picked from https://source.denx.de/u-boot/u-boot/-/commit/4b9b25d943ff95c7421cab261333fc...: 15686657 bytes read in 2726 ms (5.5 MiB/s)
If I use unsquashfs on the same board to decompress the same file using a single processor, it is much faster: # sync; echo 3 > /proc/sys/vm/drop_caches; time unsquashfs -p 1 /dev/mmcblk1p1 /boot/test-file Parallel unsquashfs: Using 1 processor 1 inodes (120 blocks) to write
[=========================================================================================================|] 120/120 100%
created 1 files created 2 directories created 0 symlinks created 0 devices created 0 fifos real 0m 0.19s user 0m 0.16s sys 0m 0.12s
Regards, Jonathan