Re: ARM imx.6 SATA speed regression

From: Gary Bisson
Date: Wed Feb 08 2017 - 12:48:50 EST


Hi Dan,

On Tue, Feb 07, 2017 at 05:02:40PM +0000, Dan MacDonald wrote:
> Thankfully there is an archive of older Arch ARM packages which should
> reduce the amount amount of bisection / compiling I may need to do and
> they have packages for most stable kernels between 4.9.0 and 4.9.8
>
> http://tardis.tiny-vps.com/aarm/packages/l/linux-armv7/

How did that go?

I've tried 'hdparm -Tt' on several kernel version and couldn't confirm
your obervations:

4.9.0:
Timing buffer-cache reads: 366 MB in 0.51 seconds = 733382 kB/s
Timing buffered disk reads: 221 MB in 3.00 seconds = 75411 kB/s

4.9.8:
Timing buffer-cache reads: 358 MB in 0.51 seconds = 717720 kB/s
Timing buffered disk reads: 221 MB in 3.00 seconds = 75244 kB/s

4.10-rc7:
Timing buffer-cache reads: 360 MB in 0.50 seconds = 723576 kB/s
Timing buffered disk reads: 244 MB in 3.00 seconds = 83024 kB/s

Are you sure rolling back to 4.9.0 improves the perf in your case?

Regards,
Gary