From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bart Van Assche <Bart.VanAssche@sandisk.com>
Subject: Re: [PATCH v2 04/13] dm-rq: Adjust requeuing delays
Date: Thu, 27 Apr 2017 19:52:44 +0000
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On Thu, 2017-04-27 at 15:16 -0400, Mike Snitzer wrote:
> This call toblk_mq_delay_run_hw_queue(), while unconvincing and suspect,
> is being introduced via block core during the 4.12 merge.
> 
> But in general, this tweaking of the timeouts in such a short period
> speaks to indecision and leaves me unconvinced of what the _best_ values
> to use are.
> 
> Let's revisit this after the merge window closes, we can tweak the 100ms
> up to 500ms in both locations if you _really_ prefer that.

Hello Mike,

The 100ms was a copy/paste from the SCSI initiator code. Later I realized
that that is too fast in the dm core, e.g. when the underlying paths are
busy due to SCSI error handling.

Bart.