syslog

[Tan Shirley]

Hi,

Anyone has any idea why my syslog contains lots of the following messages ?

vmunix: sysmap: rmap ovflo, lost

What actually went wrong ?
Thanks in advance !

[Scott Van Kalken]

This should help with your situation, as this thread mentions it's covered in DOC ID:

sysmap: rmap ovflo error DocId: KBRC00000293 Updated: 5/8/00 11:17:30 AM


http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xebf3911284f5d5118ff40090279cd0f9,00.html


hope this helps

Scott.

[Steve Steel]

Hi

see http://aa11.cjb.net/hpux_admin/1997/0446.html


That is a good explanation.

>The sysmap being referred to here is the resource map (rmap) which
>is used by the kernel to allcoate pages of virtual memory to various
>kernel-related processes. An rmap overflow is typically the result
>of fragmentation: where kernel virutal memory is being freed in
>many small, non-contiguous chunks which cannot be combined into
>free areas. Since a resource map structure contains an entry for
>each contiguous chunk of free virtual memory, the more fragmentation
>that exists, the more discreet chunks of memory must be managed,
>which may overflow the finite resource map.
>
>All that said, there's three things you can do about this:
>
> 1- ignore it: it's basically a small memory leak, as virtual
> addresses fall off the end of the map and cannot be used again.
> Since they're virutal addresses, however, and there are no other
> resources associated with them, this will not impact your system
> unless you're bothered by the warning messages or if a later
> allocation fails due to a lack of virutal space.
>
> 2- figure-out which application is causing kernel virutal memory to
> become so fragmented as to cause this problem, and get it to
> due better garbage collection.
>
> 3- Increase the size of the resource map so that less will be lost.
> The sysmap rmap defaults to a minimum of 800 entries, but will
> scale up to 2*nproc. So, increasing the size of nproc will
> increase the size of the rmap. If it's possible to increase nproc
> without causing other adverse effects, this is probably the best
> solution.




Steve steel