Lustre discuss - May 2006 - 2.6.15 kernel patches

On Feb 17, 2006  20:31 +0100, Roland Fehrenbacher wrote:
> is anybody working on kernel patches for 2.6.15.x or 2.6.16.x? It
> would be great if we could always keep the patches in sync with new
> kernel releases.
While this is a desirable goal, the effort in doing so is just too
much.  Many customers use older kernels because of stability and
the time of updating thousands of nodes frequently is non-trivial.
Also, most customers use vendor-supported kernels, so we also stick
with these kernels.

In other news, we are hard at work (and fairly close) to being able
to run a client (not server yet) on an unpatched kernel.  While the
performance may not be as good as a patched kernel (because of the
need to do multiple RPCs for some operations) it will be useful
for those environments where patching the kernel is undesirable.

We will also work toward getting the "optimized" patches into the
kernel, but that is a very slow process.
> PS: I know about bugzilla bug# 9421. Unfortunately, the patches
> working with 2.6.13.x have a lot of failed hunks when applied to
> 2.6.15.
I thought they had updated for the 2.6.14 kernel also?  In any case,
I believe there is a page on the Lustre wiki with unsupported non-CFS
patches for other kernels.  Also, there is a Lustre User group page
with such patches, but they appear to be only at 2.6.12 also (though
I''m sure they would appreciate any contributions from you):

http://www.lustreusers.org/download.html

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.

>>>>> "Andreas" == Andreas Dilger
<adilger@clusterfs.com> writes:
    Andreas> On Feb 17, 2006 20:31 +0100, Roland Fehrenbacher wrote:
    >> is anybody working on kernel patches for 2.6.15.x or 2.6.16.x? 
    >> It would be great if we could always keep the patches in sync
    >> with new kernel releases.

    Andreas> While this is a desirable goal, the effort in doing so is
    Andreas> just too much.  Many customers use older kernels because
    Andreas> of stability and the time of updating thousands of nodes
    Andreas> frequently is non-trivial.  Also, most customers use
    Andreas> vendor-supported kernels, so we also stick with these
    Andreas> kernels.

Problem is that those old kernels require quite a number of patches
too for certain hardware/features that we require.

    Andreas> In other news, we are hard at work (and fairly close) to
    Andreas> being able to run a client (not server yet) on an
    Andreas> unpatched kernel.  While the performance may not be as
    Andreas> good as a patched kernel (because of the need to do
    Andreas> multiple RPCs for some operations) it will be useful for
    Andreas> those environments where patching the kernel is
    Andreas> undesirable.

That''s good news.

    Andreas> We will also work toward getting the "optimized"
patches
    Andreas> into the kernel, but that is a very slow process.

Will you help me out with some of the more critical changes? It would
be great if someone with first-hand knowledge could have a look at
the changes I''ll come up with. There are quite a few new
functions/procedures that were added as replacement for other ones in
2.6.14/2.6.15, and getting them patched right will be the tough part.

    >> PS: I know about bugzilla bug# 9421. Unfortunately, the patches
    >> working with 2.6.13.x have a lot of failed hunks when applied
    >> to
    >> 2.6.15.

    Andreas> I thought they had updated for the 2.6.14 kernel also?

Initially that was the goal, but it was never done, at least not to my
knowledge. 

    Andreas> In any case, I believe there is a page on the Lustre wiki
    Andreas> with unsupported non-CFS patches for other kernels.
    Andreas> Also, there is a Lustre User group page with such
    Andreas> patches, but they appear to be only at 2.6.12 also
    Andreas> (though I''m sure they would appreciate any
contributions
    Andreas> from you):

    Andreas> http://www.lustreusers.org/download.html

Nothing more recent than 2.6.12 unfortunately.

Cheers,

Roland

Hi,

is anybody working on kernel patches for 2.6.15.x or 2.6.16.x? It
would be great if we could always keep the patches in sync with new
kernel releases. I''m starting to port the 2.6.12 patches to 2.6.15.x,
but would appreciate any help in doing so.

PS: I know about bugzilla bug# 9421. Unfortunately, the patches
working with 2.6.13.x have a lot of failed hunks when applied to
2.6.15.

Roland