Re: [PATCH v3 2/2] zonefs: Add documentation

From: Damien Le Moal
Date: Wed Dec 25 2019 - 01:40:40 EST


On 2019/12/25 10:33, Randy Dunlap wrote:
[...]
>> +For sequential write zone files, the file size changes as data is appended at
>> +the end of the file, similarly to any regular file system.
>> +
>> +# dd if=/dev/zero of=/mnt/seq/0 bs=4096 count=1 conv=notrunc oflag=direct
>> +1+0 records in
>> +1+0 records out
>> +4096 bytes (4.1 kB, 4.0 KiB) copied, 1.05112 s, 3.9 kB/s
>
> why so slow?
>
>> +
>> +# ls -l /mnt/seq/0
>> +-rw-r----- 1 root root 4096 Nov 25 13:23 /mnt/sdh/seq/0
>
> I don't understand the "sdh/" here. Please explain for me (not necessarily
> in the doc file).

The drive I used for generating the example was /dev/sdh and it was in
fact mounted under /mnt/sdh/ for the test, but I removed "sdh" from the
pasted commands and results to make things simpler. I forgot to remove
the drive name on this line. Fixed now.

Thank you for the review.

--
Damien Le Moal
Western Digital Research