Fancy trying if it would behave differently with the NCQ branch?
Jaromir
2017-07-03 6:34 GMT+02:00 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