KMAP ENTRY limit

[Vincent Jardin]

Hi,

I get a FreeBSD 4.8 that reaches the limit of KMAP ENTRY whereas it remains 
enough free memory. How is computed this limit and how can it be increased ?

$ vmstat -z
ITEM            SIZE     LIMIT    USED    FREE  REQUESTS
  ...
KMAP ENTRY:       48,     7933,    130,    168,     1037
(panic when SIZE >= LIMIT)

Moreover, why should vm_map_entry_create() panic when zalloc() returns NULL ? 
I think one can return NULL without panicing. Is it a bug or a feature ?

Regards,
  Vincent