ia64 emulator or test machine available

ia64 emulator or test machine available

[Nick Piggin]

Hi,

I have been doing some work in the area of page table lock reduction
in collaboration with Christoph Lameter. The main aim of this is to
improve multi-threaded page fault performance, but may also benefit
other areas, like multi threded futex performance, and page reclaim.

I have working implementations on i386 and x86-64, and now I would like
to get an ia64 version running. For two reasons: first, SGI is pushing
most of the work in this area, obviously for their ia64 systems;

second, ia64's implementation of pte access faults in software means
there is a possibility to implement mutual exclusion for pte access with
pte lock bits rather than cmpxchg, and with no downside. pte lock bits
may prove to be more scalable than cmpxchg in some areas.

With the help of Keith and Christoph, we have a version that is close
to booting - however I can't ask or expect them to debug my bugs. So if
anyone is interested in giving me access to an emulator or (preferably)
machine with serial console and power access that boots recent 2.6
kernels then I would be much obliged.

I wouldn't require anything fancy, nor for (hopefully) too long a time.

Thanks,
Nick

Re: ia64 emulator or test machine available

[Darren Williams]

Hi Nick

On Sat, 27 Nov 2004, Nick Piggin wrote:

> Hi,
> 
> I have been doing some work in the area of page table lock reduction
> in collaboration with Christoph Lameter. The main aim of this is to
> improve multi-threaded page fault performance, but may also benefit
> other areas, like multi threded futex performance, and page reclaim.
> 
> I have working implementations on i386 and x86-64, and now I would like
> to get an ia64 version running. For two reasons: first, SGI is pushing
> most of the work in this area, obviously for their ia64 systems;
> 
> second, ia64's implementation of pte access faults in software means
> there is a possibility to implement mutual exclusion for pte access with
> pte lock bits rather than cmpxchg, and with no downside. pte lock bits
> may prove to be more scalable than cmpxchg in some areas.
> 
> With the help of Keith and Christoph, we have a version that is close
> to booting - however I can't ask or expect them to debug my bugs. So if
> anyone is interested in giving me access to an emulator or (preferably)
> machine with serial console and power access that boots recent 2.6
> kernels then I would be much obliged.
> 
> I wouldn't require anything fancy, nor for (hopefully) too long a time.
Possibly the best place to start debugging would be on the Ia64 SKI
simulator, http://www.hpl.hp.com/research/linux/ski/index.php.

Current 2.6 kernel boots and runs. Use 'sim_defconfig' for initial
configuration.

> 
> Thanks,
> Nick
> -
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--------------------------------------------------
Darren Williams <dsw AT gelato.unsw.edu.au>
Gelato@UNSW <www.gelato.unsw.edu.au>
--------------------------------------------------

Re: ia64 emulator or test machine available

[Nick Piggin]

Darren Williams wrote:

> 
> Possibly the best place to start debugging would be on the Ia64 SKI
> simulator, http://www.hpl.hp.com/research/linux/ski/index.php.
> 
> Current 2.6 kernel boots and runs. Use 'sim_defconfig' for initial
> configuration.
> 

Thanks Darren, and everyone else who kindly replied.

The simulator looks interesting - I will look into that.

I have been given access to an ia64 system that has been sufficient
for some basic testing. Thank you all for your generosity.


Nick