[WBEL-users] kernel 2.6.5 on WB 3.0?

[Terrence Martin]

Bill Davidsen wrote:

> Seth Bardash wrote:
>
>> Any suggestions on the packages that need to be upgraded or added
>> to WB 3.0 to get it to support 2.6.5 would be helpful. 
>
>
> You need the modutils to load modules. The arjan ones are more 
> convenient than doing the install of Rusty'd code yourself, if nothing 
> else. Careful, there's a WBEL upgrade which overwrites them again.
>
> For the proc utils, you can use the RH ones or the Albert Callahan 
> sourceforge version. I slightly prefer the AC/SF versions, both work 
> and differ mainly in user presentation of data.
>
>>
>> We are going to try to start where arjanv/2.6 has left off. Just
>> installing 2.6.5 source and doing the make's doesn't come close.
>> Way too many unresolved symbols and you need to install the
>> filesystem drivers in the kernel to get them to come up properly.
>
>
> The main thing which seems to be missing in arjan and kernel.org 
> versions is a forward port of the CPIE stuff for VPN. That's the only 
> thing I don't find which I would really like, since I've used it a 
> bit. Yes there are alternatives.
>
>>
>> If there was something that did for error messages what rpm -q
>> does packages that would be a big help but its not that easy....
>>
>> We have found that systems based on Fedora core 1 upgraded to the
>> 2.6.5 kernel run the gigabit ethernet about 25 to 40 % faster than
>> the standard 2.4.XX kernel with no other changes. 33-40 MB/sec
>> versus 52 - 60 MB/sec - The only changes made were to install the
>> source for 2.6.5, compile and run the new kernel (greatly
>> sinplified of course). All hardware and BIOS setting were the
>> same. The numbers shown above were for nfs transfers of iso images
>> to and from our linux server.
>
>
> Were you using a "standard kerenl" as in kernel.org, or the enhanced 
> one in WBEL? That had new threading as well.
>
>>
>> If we could upgrade the WB 3.0 kernel to 2.6.5 with the correct
>> additional rpm packages to get it to work correctly we expect to
>> see a similar increase in net performance.
>>
>> Something to work on in my spare time ;-)
>
>
> I strongly believe that this is a case of better tuning by default 
> rather than some driver thing, but I could be wrong about that.
>
These numbers for gigabit networking similar to what we find. We tune 
both 2.4 and 2.6 as much as possible for gigabit. We have realized a 
significant (30%) speedup on gigabit networking using identical tunings 
with 2.4 vs 2.6. In particular in our dual gigabit network card tests we 
get upwards of 200MB/s.  For our testing we have used Fedora Core, but I 
am moving to WBEL or Rocks Cluster 3.1+ (uses RHEL3 as a base) for our 
cluster so will be attempting to deploy 2.6 on those systems.

What I have also found is that the IO is also around 20% better on 2.6.4 
than on stock redhat kernels in Fedora when reading and writing to a 
fiberchannel attached storage array.  I  attribute this to the IO 
scheduler improvements in 2.6 not available in redhat 2.4 kernels.

There are also other features that are attractive, especially for 
clusters. NFSv4, as well as support for PVFS2.

Terrence