2008-10-15 01:52:36

by Wildman, Tom

[permalink] [raw]
Subject: Superpages Project - sourceforge.net/projects/linuxsuperpages


A new project has been created at SourceForge with an implementation of the Rice University's Superpages FreeBSD prototype that has been ported to the 2.6 Linux kernel for IA64, x86-64, and x86-32.

The project can be found at: http://sourceforge.net/projects/linuxsuperpages

The major benefit of supporting Superpages is increased memory reach of the processor's TLB, which reduces the number of TLB misses in applications that have large data sets. Some benchmarks have been improved 20% in execution time.

Reference http://www.cs.rice.edu/~jnavarro/superpages/ for more information about the Rice University's Superpages project.

The project is being made available to the Open Source community to share the implementation and knowledge. With the enhancements to the x86 architectures to support multiple and large page sizes there should be increased interest in this functionality.

/Tom

Tom Wildman
Hewlett-Packard Company
200 Forest Street Phone: 978.841.7648
Marlboro, MA 01752 Email: [email protected]


2008-10-15 08:30:11

by Alan Jenkins

[permalink] [raw]
Subject: Re: Superpages Project - sourceforge.net/projects/linuxsuperpages

Wildman, Tom wrote:
> A new project has been created at SourceForge with an implementation of the Rice University's Superpages FreeBSD prototype that has been ported to the 2.6 Linux kernel for IA64, x86-64, and x86-32.
>
> The project can be found at: http://sourceforge.net/projects/linuxsuperpages
>

Maybe I'm just struggling with the re-designed Sourceforge, but I can't
find a link to the "Wiki section" mentioned in the summary.

> The major benefit of supporting Superpages is increased memory reach of the processor's TLB, which reduces the number of TLB misses in applications that have large data sets. Some benchmarks have been improved 20% in execution time.
>
> Reference http://www.cs.rice.edu/~jnavarro/superpages/ for more information about the Rice University's Superpages project.
>
> The project is being made available to the Open Source community to share the implementation and knowledge. With the enhancements to the x86 architectures to support multiple and large page sizes there should be increased interest in this functionality.
>
> /Tom
>

2008-10-15 08:53:18

by Bert Wesarg

[permalink] [raw]
Subject: Re: Superpages Project - sourceforge.net/projects/linuxsuperpages

On Wed, Oct 15, 2008 at 10:29, Alan Jenkins <[email protected]> wrote:
> Wildman, Tom wrote:
>> A new project has been created at SourceForge with an implementation of the Rice University's Superpages FreeBSD prototype that has been ported to the 2.6 Linux kernel for IA64, x86-64, and x86-32.
>>
>> The project can be found at: http://sourceforge.net/projects/linuxsuperpages
>>
>
> Maybe I'm just struggling with the re-designed Sourceforge, but I can't
> find a link to the "Wiki section" mentioned in the summary.
Click "More" in the menu bar, right of "Summary", "Tracker", "Forums",
and "Download".

2008-10-15 11:18:26

by Wildman, Tom

[permalink] [raw]
Subject: RE: Superpages Project - sourceforge.net/projects/linuxsuperpages


Alan,

I agree that it is not easy to find so I will add a link to the wiki section on the front page (if possible).

http://linuxsuperpages.wiki.sourceforge.net/

/Tom

-----Original Message-----
From: Alan Jenkins [mailto:[email protected]] On Behalf Of Alan Jenkins
Sent: Wednesday, October 15, 2008 4:30 AM
To: Wildman, Tom
Cc: [email protected]; [email protected]; [email protected]
Subject: Re: Superpages Project - sourceforge.net/projects/linuxsuperpages

Wildman, Tom wrote:
> A new project has been created at SourceForge with an implementation of the Rice University's Superpages FreeBSD prototype that has been ported to the 2.6 Linux kernel for IA64, x86-64, and x86-32.
>
> The project can be found at:
> http://sourceforge.net/projects/linuxsuperpages
>

Maybe I'm just struggling with the re-designed Sourceforge, but I can't find a link to the "Wiki section" mentioned in the summary.

> The major benefit of supporting Superpages is increased memory reach of the processor's TLB, which reduces the number of TLB misses in applications that have large data sets. Some benchmarks have been improved 20% in execution time.
>
> Reference http://www.cs.rice.edu/~jnavarro/superpages/ for more information about the Rice University's Superpages project.
>
> The project is being made available to the Open Source community to share the implementation and knowledge. With the enhancements to the x86 architectures to support multiple and large page sizes there should be increased interest in this functionality.
>
> /Tom
>

2008-10-15 13:00:57

by Peter Zijlstra

[permalink] [raw]
Subject: Re: Superpages Project - sourceforge.net/projects/linuxsuperpages

On Wed, 2008-10-15 at 01:51 +0000, Wildman, Tom wrote:
> A new project has been created at SourceForge with an implementation
> of the Rice University's Superpages FreeBSD prototype that has been
> ported to the 2.6 Linux kernel for IA64, x86-64, and x86-32.
>
> The project can be found at:
> http://sourceforge.net/projects/linuxsuperpages
>
> The major benefit of supporting Superpages is increased memory reach
> of the processor's TLB, which reduces the number of TLB misses in
> applications that have large data sets. Some benchmarks have been
> improved 20% in execution time.
>
> Reference http://www.cs.rice.edu/~jnavarro/superpages/ for more information
> about the Rice University's Superpages project.
>
> The project is being made available to the Open Source community to
> share the implementation and knowledge. With the enhancements to the
> x86 architectures to support multiple and large page sizes there
> should be increased interest in this functionality.

How are you proposing to address the fun issues like online compaction
etc. ?

Furthermore, what's the added advantage of dynamic superpages over
exlpicit superpage support, eg. though the use of libhugetlb?

Unless you realize online compaction and add a kind of extend allocation
to the page allocator there will hardly ever be a situation where you
can promote a page.

All of which is rather expensive to do, changing the application might
be easier and deliver better performance gains.