From mboxrd@z Thu Jan  1 00:00:00 1970
From: hch@infradead.org (Christoph Hellwig)
Date: Fri, 26 May 2017 02:25:56 -0700
Subject: NVMe APST high latency power states being skipped
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On Thu, May 25, 2017@04:21:07PM +0800, Kai-Heng Feng wrote:
> I did some benchmark on the high latency SanDisk A400:
> Kernel compilation, no PS3/PS4:
> real    23m36.466s
> user    115m49.944s
> sys     10m58.352s
> 
> Kernel compilation, allow PS3/PS4:
> real    24m40.308s
> user    116m12.600s
> sys     11m47.484s

That's quite a bit of a slow down.  Can we play a bit with the
entry latency (maybe just for PS4) so that we still get into the
modes, but not as quickly?