Re: HEADS-UP: SATA NCQ support merged (from jdolecek-ncq branch)

[Michael <macallan%netbsd.org@localhost>]

Hello,

On Sat, 7 Oct 2017 18:34:04 +0200
Jaromír Doleček <jaromir.dolecek%gmail.com@localhost> wrote:

> I've merged the NCQ branch to HEAD.

Nice, thanks!

> The code was quite extensively tested on that harware on amd64. Other archs
> and drivers compile, but I had no way to test them. Particularily, I had no
> chance to really test any real IDE disks, neither any non-PCI controller
> attachments. If you are in position to confirm them working, I'd appreciate
> it.

I tried siisata on sparc64 ( in a 64bit/66MHz slot ) and ahcisata on a
Cubietruck, both seem to work as intended.

> Please report any problems, I'll fix any potential fallout ASAP.
> 
> Performance wise, I've tested so far only sequential I/O via fio and dd
> with cache enabled. I observed very mild (>2%, 72.7->74.8 MB/s) performance
> increase for spinning rust HDD, but quite big increase for SSD (350->450
> MB/s). With disabled disk cache, or random I/O, NCQ will probably have more
> effect.

I tried sequential reads ( dd if=/dev/rwd0c ... ) and throughput took a
significant hit. I used to get about 120MB/s with the siisata, now it
fluctuates between 80 and 90MB/s, ahcisata dropped from about 80MB/s to
70MB/s. Both spinning rust of varying vintage.
I should probably do a bonnie run on either one before & after to see
if there's any change in random access.

have fun
Michael