64-bit Linux Binary Compatibility (for Matlab)

[Maxim Khitrov]

Hello all,

Simple question - am I able to run 64-bit linux binaries using the ABI
emulation under FreeBSD 7.0 amd64? In the NOTES for amd64 kernel
configuration the COMPAT_LINUX option is commented out, but I don't
understand the explanation at the top of the section:

#XXX keep these here for now and reactivate when support for emulating
#XXX these 32 bit binaries is added.

For 32-bit there is already the COMPAT_LINUX32 option, no? This is the
first time that I've dealt with linux compatibility in FreeBSD, so
would appreciate some pointers. The goal is to get Matlab running in
64-bit mode. Some of the algorithms that my colleagues need to execute
were crashing the software, and they assumed that it was due to a
limitation of virtual memory that is available under 32-bit.
Apparently Matlab tries to allocate a continuous chunk of memory, and
we needed to upgrade to 64-bit hardware to give it access to more than
1GB of memory, which is about the most that it was able to get before.
It's a lousy explanation, but I wasn't employed at this place when
this diagnosis was made.

If anyone else here is running Matlab on FreeBSD, I'd welcome any
pointers you can give me for setting it up. Right now, I'm following
the steps listed in the handbook. As a side note - is it, in fact, the
case that Matlab x86_64 will run slower than the 32-bit version
(http://osdir.com/ml/netbsd.ports.x86-64/2006-07/msg00061.html)?

- Max