Linux kernel recommendations for HBase 0.94.2

[Michael Ellery <me...@opendns.com>]

We are currently building a cluster based on CDH4.2 (HBase 0.94.2). We are trying to decide whether to use a 3.8 kernel or stick with our current 3.2 kernel. Does anyone have operational experience with either kernel version and HBase that indicates to a version preference? Are there specific recommended kernel tuning params in either kernel version that we should consider? 

Any advice appreciated.

-Mike Ellery

Re: Linux kernel recommendations for HBase 0.94.2

[Pal Konyves <pa...@gmail.com>]

I think the newer kernels in the last several years contain mostly new
features/drivers rather than optimizations. Plus JVM puts another
abstraction between the application and the kernel which makes which makes
any kernel specific consideations in terms of HBase much less sensible.
I don't think you will see any different between 3.8 and 3.2.

Unfortunatelly I'm not a kernel tuning guy. It's a nice idea to tune the
kernel for an application, and you may gain some performance in some cases,
but in my opinion it's unlikely that you get e.g. more than a couple
percentage of performance gain overall. Good performance comes from good
program. If you wish to tune, probably go for I/O specific settings. What I
can recommend  however is to recompile the kernel for your CPU, that way
some CPU specific instructions can bring some performance.


On Tue, Apr 2, 2013 at 8:34 PM, Michael Ellery <me...@opendns.com> wrote:

> We are currently building a cluster based on CDH4.2 (HBase 0.94.2). We are
> trying to decide whether to use a 3.8 kernel or stick with our current 3.2
> kernel. Does anyone have operational experience with either kernel version
> and HBase that indicates to a version preference? Are there specific
> recommended kernel tuning params in either kernel version that we should
> consider?
>
> Any advice appreciated.
>
> -Mike Ellery