[dm-devel] [PATCH 0/2] multipath-tools/libmultipath: Support for the native NVMe Ioctl command and add args min_avg_latency for path_latency.

[Martin Wilck]

On Fri, 2017-07-14 at 09:47 +0800, Yang Feng wrote:
> Hi Xose,
> 
> But tur can not support NVMe device, and if the default checker
> change to ping,
> then it can support NVMe device by a keep alive command and SCSI
> device by a
> tur command.

I agree with Xose. This is what we have the hwtable for. It's a good
and necessary thing to implement a checker equivalent to TUR for NVME,
but not a reason to remove TUR. SCSI is going to stay for some time to
come.

As for the path latency checker and your readsector0 function, I don't
quite understand why you are using SG_IO at all. Why can't you just
read() with O_DIRECT?

Saying that without having had the time for a deeper review of your
patch.

Martin
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Dr. Martin Wilck <mwilck at suse.com>, Tel. +49 (0)911 74053 2107
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