Re: 2.6.8.1 mempool subsystem sickness

[Nick Piggin <nickpiggin@yahoo.com.au>]

jmerkey@comcast.net wrote:
> On a system with 4GB of memory, and without 
> the user space patch that spilts user space
> just a stock kernel, I am seeing memory 
> allocation failures with X server and simple
> apps on a machine with a Pentium 4 
> processor and 500MB of memory.  
> 
> If you load large apps and do a lot of 
> skb traffic, the mempool abd slab 
> caches start gobbling up pages
> and don't seem to balance them 
> very well, resulting in memory 
> allocation failures over time if
> the system stays up for a week 
> or more.  
> 
> I am also seeing the same behavior 
> on another system which has been
> running for almost 30 days with 
> an skb based traffic regeneration 
> test calling and sending skb's
> in kernel between two interfaces.
> 
> The pages over time get stuck 
> in the slab allocator and user
> space apps start to fail on alloc
> requests.  
> 
> Rebooting the system clears
> the problem, which slowly over time
> comes back.  I am seeing this with
> stock kernels from kernel.org 
> and on kernels I have patched,
> so the problem seems to be
> in the base code.  I have spent
> the last two weeks observing 
> the problem to verify I can
> reproduce it and it keeps 
> happening.  
> 
> Jeff
> 

Hi Jeff,
Can you give us a few more details please? Post the allocation failure
messages in full, and post /proc/meminfo, etc. Thanks.