Re: [PATCH] scsi: core: Log SCSI command age with errors

[Martin Wilck]

On Fri, 2019-09-27 at 13:45 -0400, Laurence Oberman wrote:
> 
> Hi Martin
> 
> Agreed about log extraction, but turning that on with a busy workload
> in a production environment is not practical. We cant do it with
> systems with 1000's of luns and 1000's of IOPS/sec.
> Also second resolution is good enough for the debug we want to see.

I gather that you look at a specific problem where second resolution is
sufficient. For upstream, the generic usefulness should be considered,
and I don't think we can say today that better-than-second resolution
will never be useful, so I still vote for milliseconds.

Wrt the enablement of the option on highly loaded systems, I'm not sure
I understand. You need to enable SCSI logging anyway, don't you? Is it
an issue to have to set 2 sysfs values rather than just one?

Regards,
Martin

> 
> Regards
> Laurence
>