xfs - high CPU usage when removing files

[Stefan Ring]

>> I noticed a high CPU usage when removing files from XFS partition on Linux,
>> CentOS (always close to 100%).
>> Is it a known issue, or is it more likely to be attributed to my testing
>> methodology ('time' command)?
>
> If you are removing extremely fragmented files, then 100% CPU will
> be seen.  If you are removing tens of thousands of small files, then
> 100% CPU will be seen,
>
> IOWs, if there's enough work to be done, removing files will use all
> the available CPU. There's no problem with that.

Also, removing huge files which are completely in cache (recently
written, for example) will use considerable CPU time.