Re: kswapd & 2.4.21-47.0.0.1

[Konstantin Kalin <konstantin.kalin@gmail.com>]

Well. I expected similar answer :) But unfortunately it's not my 
decision to use CentOS. Also I couldn't get RH customer support for some 
reasons.
So anyway thank you for answer.

Regards,
Kostya.

Willy Tarreau wrote:
> Hello,
>
> On Wed, Mar 14, 2007 at 04:35:55PM +0300, Konstantin Kalin wrote:
>   
>> Hello, All
>>
>> I have the following configuration: CentOS 3.8, kernel 
>> 2.4.21-41.0.01.EL, Dialogic boards.
>> Sometimes a kernel panic happens. I setup netdump and got several crash 
>> dumps and logs. Backtrace shows that kswapd called BUG in try_to_unmap 
>> function. Unfortunately I couldn't upgrade the kernel because of 
>> proprietary Dialogic drivers which are precompiled.
>>
>> Could somebody help me? I tried to find similar issues in maillist and 
>> failed with it. There are a few messages but they describe another case.
>>     
>
> Well, I think you're trying to get both the cake and the money for it.
> You use a vendor-specific stable kernel in order to get a high reliability
> and good hardware support, but without paying for the customer support
> associated with it, and when you have a problem you ask for free help
> here where people don't know much about it (except for those who worked
> on it).
>
> By trying to get all advantages, you're in the worst situation : you have
> a bug with a kernel that nobody knows except the vendor, and you can't
> beat the vendor for this. I don't know if CentOS offers community-based
> support through mailing lists or such, but maybe you'd loose less time
> and money by buying the smallest support contract from RH and ask them
> to help you on this problem.
>
>   
>> As I understand the rmap.c are under active development and it's 
>> strongly been changing per each kernel version. Also if I understand 
>> correct rmap.c has appeared in the kernel 2.6.x and my version of the 
>> kernel is a backport by RedHat from 2.6 to 2.4.
>>     
>
> Nope, it was initially written for 2.4 by Rik van Riel, and supported
> for a long time as a patch for these kernels. Later it got merged in
> 2.4-ac which became a base for RHEL3. It was also merged in 2.6 but
> I believe that it got important changes, though I'm not sure.
>
>   
>> Information about the crash is below. The specific of my system is a lot 
>> of java thread (up to 1500).
>>     
>
> I'm not sure that many people here will be able to provide you with much
> help, unfortunately.
>
> Regards,
> Willy
>
>
>
>
>