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[[!tag faq/support]]

[[!meta title="830 MiB RAM Limit"]]

The 830MB RAM limit has been removed, but just like any 32-bit OS without bad tricks,
GNU Mach can not cope well with lots of memory.  Latest versions of the Debian `gnumach`
package will limit themselves to 3 GiB of memory. If you want more, you can twiddle
the `VM_MAX_ADDRESS` limit between kernelland and userland in
`i386/include/mach/i386/vm_param.h`, but glibc and the hurd servers will not cope
well with less than 1 GB.

There is a [[64-bit port|open_issues/64-bit_port]] in progress.

If you have an older version, or still experience problems with `vmstat` (see
above) reported much less memory than you have, the best is to limit the memory
it can see via GRUB's `upppermem` feature.  Add `uppermem 786432` to GRUB's Hurd
entry in `menu.lst`.