Re: PM related performance degradation on OMAP3

[Kevin Hilman <khilman@ti.com>]

Gary Thomas <gary@mlbassoc.com> writes:

> On 2012-04-11 13:17, Kevin Hilman wrote:
>> Gary Thomas<gary@mlbassoc.com>  writes:
>>
>> [...]
>>
>>> I fear I'm seeing similar problems with 3.3.  I have my board (similar
>>> to the BeagleBoard) ported to 3.0 and 3.3.  I'm seeing terrible network
>>> performance on 3.3.  For example, if I use TFTP to download a large file
>>> (~35MB), I get this:
>>>    3.0:  42.5 sec
>>>    3.3: 625.0 sec
>>> That's a factor of 15 worse!
>>
>> This might not be the same problem.  What is the NIC being used, and
>> does it have GPIO interrupts?
>
> My board uses SMSC911x with GPIO interrupt signal.

OK, then your problem is almost certainly solved by my GPIO triggering
fix, and not related to Grazvytas' problem.

>>
>> If it's using GPIO interrupts, then you likely need this patch from
>> mainline (v3.4-rc1)
>
> I tried to just pick up the patch you [sort of] quoted below, but had
> a hard time applying it to my kernel. I've tried to just pick up the
> latest files from the mainline kernel, but so far I've nothing that
> builds

Oh, right.  Sorry about that.  Yeah, that patch actually has
dependencies on other GPIO changes that were queued for v3.4 (and not in
v3.3.)

If you're on v3.3, just pull the branch below[1] which is based on
v3.3-rc2.  Pulling that into a v3.3 should build just fine.

Kevin

[1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm.git for_3.4/fixes/gpio