Re: Maximum heap size?

[Dan Maas]

> If you are hitting a 1GB limit I would assume the jvm isn't very bright
> about its allocation of resources. You should run out at something like
> 2.5Gb of allocations. (you lose some to app and library maps)

Specifically, the jvm is probably getting memory from brk(), because brk()
only operates in the ~1GB region between 0x08000000 + epsilon (where the
executable ends) and 0x40000000 (where shared libs begin). The easiest way
to get more than 1GB is to mmap() anonymous pages (which will come from the
remaining ~2GB region between 0x40000000 and 0xBFFFFFFF). e.g. glibc will
use anonymous mmap() to fulfill large malloc() requests.

Regards,
Dan