Re: [PATCH RFC 0/3] btrfs: Performance profiler support

[Nikolay Borisov <nborisov@suse.com>]

On 10.03.19 г. 5:08 ч., Anand Jain wrote:
> 
>  I agree we need btrfs specific performance measurements and its
>  my list too.
> 
>  However my idea was to add it as a btrfs-progs subcommand such as
> 
>    btrfs inspect perf ...
> 
>  And implement by using the systemtap/perf/bpf/dtrace, as these
>  can tap the kernel functions from the useland using which we
>  can measure the time taken and no kernel changes will be required.
>  But yes we need to update the btrfs-progs if we rename the kernel
>  function, which I think is ok.
> 
>  I was too early trying this with bpf before, probably there are
>  more tools now to do that same thing.

This is way too developer oriented to be included in the generic btrfs
tools. Frankly bpf makes sense but only as a separate script being
developed and possibly shared on github or whatnot so that other
interested people can use it. However, integrating with btrfs-progs
definitely seems the wrong thing to do.

On the same note - I'm highly against this patchset landing in the kernel.