= RunningOnNetBSD

MLton runs fine on http://www.netbsd.org/[NetBSD].

== Installing the correct packages for NetBSD

The NetBSD system installs 3rd party packages by a mechanism known as
pkgsrc. This is a tree of Makefiles which when invoked downloads the
source code, builds a package and installs it on the system. In order
to run MLton on NetBSD, you will have to install several packages for
it to work:

* `shells/bash`

* `devel/gmp`

* `devel/gmake`

In order to get graphical call-graphs of profiling information, you
will need the additional package

* `graphics/graphviz`

To build the documentation for MLton, you will need the addtional
package

* `textproc/asciidoc`.

== Tips for compiling and using MLton on NetBSD

MLton can be a memory-hog on computers with little memory.  While
640Mb of RAM ought to be enough to self-compile MLton one might want
to do some tuning to the NetBSD VM subsystem in order to succeed.  The
notes presented here is what <<JesperLouisAndersen#>> uses for
compiling MLton on his laptop.

=== The NetBSD VM subsystem

NetBSD uses a VM subsystem named
http://www.ccrc.wustl.edu/pub/chuck/tech/uvm/[UVM].
http://www.selonen.org/arto/netbsd/vm_tune.html[Tuning the VM system]
can be done via the `sysctl(8)`-interface with the "VM" MIB set.

=== Tuning the NetBSD VM subsystem for MLton

MLton uses a lot of anonymous pages when it is running. Thus, we will
need to tune up the default of 80 for anonymous pages.  Setting

----
sysctl -w vm.anonmax=95
sysctl -w vm.anonmin=50
sysctl -w vm.filemin=2
sysctl -w vm.execmin=2
sysctl -w vm.filemax=4
sysctl -w vm.execmax=4
----

makes it less likely for the VM system to swap out anonymous pages.
For a full explanation of the above flags, see the documentation.

The result is that my laptop goes from a MLton compile where it swaps
a lot to a MLton compile with no swapping.
