Problem in EROFS: Not able to read the files after mount

Gao Xiang hsiangkao at aol.com
Wed Jan 29 15:59:52 AEDT 2020


On Wed, Jan 29, 2020 at 09:43:37AM +0530, Saumya Panda wrote:
> 
> localhost:~> fio --name=randread --ioengine=libaio --iodepth=16
> --rw=randread --bs=4k --direct=0 --size=512M --numjobs=4 --runtime=240
> --group_reporting --filename=/mnt/enwik9_erofs/enwik9
> 
> randread: (g=0): rw=randread, bs=(R) 4096B-4096B, (W) 4096B-4096B, (T)
> 4096B-4096B, ioengine=libaio, iodepth=16

And I don't think such configuration is useful to calculate read ampfication
since you read 100% finally, use multi-thread without memory limitation (all
compressed data will be cached, so the total read is compressed size).

I have no idea what you want to get via doing comparsion between EROFS and
Squashfs. Larger block size much like readahead in bulk. If you benchmark
uncompressed file systems, you will notice such filesystems cannot get such
high 100% randread number.

Thank,
Gao Xiang



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