Re: AMD Ryzen and NetBSD?

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Sun, Jul 02, 2017 at 10:57:20PM +0100, Patrick Welche wrote:
> On Fri, Jun 30, 2017 at 12:00:45PM -0400, Thor Lancelot Simon wrote:
> 
> I shoved a rather newer ST2000DM001-1CH164 in, which according to its
> marketing bumpf can manage "Max SustainableTransfer Rate 210MB/s"
> and not so bad:
> 
> # dd if=/dev/zero ibs=64k | progress -l 976751887b dd of=/dev/rdk15 obs=64
> k
>  99% |********************************** |   465 GiB  116.74 MiB/s    00:00 ETAd

This is already effectively double buffered, because of the way you used
"progress".  You could try using a larger blocksize for the reads from
/dev/zero (1m perhaps) and also for the writes to rdk15 - the kernel
will buffer up and dispatch the MAXPHYS sized I/Os.

To get 200MB out of that drive you likely need larger writes, which we
currently can't do.  It might perform slightly better through the
filesystem, though.

Thor