panic: kmem_map too small

[Robert Watson]

On Thu, 26 Oct 2006, Stefan Bethke wrote:

>           acpica         3024          159K     20026966
...
> db> show uma
>             Zone       Allocs        Frees         Used    Cache
>               64      9990754      9986054         4700  9980755

Looks like acpica has gone crazy performing allocation/freeing at a very high 
rate, and that for some reason, UMA is failing to properly reuse/release 
memory.  So there are two bugs/problems here: whatever is causing ACPI to 
behave this way, and then the fact that UMA is failing to deal properly with 
its misbehavior.  Alternatively, that we have a bug in the way statistics are 
handled.  If you can generate a coredump, it would be quite useful to be able 
to run umstat (src/tools/tools/umastat in HEAD) on it.  The tool probably 
needs a bit of tweaking to run on the core dump -- in particular, the first 
and second arguments of kvm_open() need to be the name of the kernel and 
dumpfile, rather than NULL.  This would help confirm what actual state UMA is 
in.

Robert N M Watson
Computer Laboratory
University of Cambridge