(From Cygwin's User Guide): By default, no Cygwin program can allocate more than 384 MB of memory (program and data).
You should not need to change this default in most circumstances. However, if you need
to use more real or virtual memory in your machine you may add an entry in either the
HKEY_LOCAL_MACHINE (to change the limit for all users) or HKEY_CURRENT_USER (for just
the current user) section of the registry. Add the DWORD value heap_chunk_in_mb and set
it to the desired memory limit in decimal MB. It is preferred to do this in Cygwin
using the regtool program included in the Cygwin package. (For more information about
regtool or the other Cygwin utilities, see the Section called Cygwin Utilities in
Chapter 3 or use the --help option of each utility.) You should always be careful
when using regtool since damaging your system registry can result in an unusable system.
This example sets memory limit to 1024 MB:
regtool -i set /HKLM/Software/Cygnus\ Solutions/Cygwin/heap_chunk_in_mb 1024
regtool -v list /HKLM/Software/Cygnus\ Solutions/Cygwin