On Jan 9, 6:41 pm, Sion Arrowsmith <si... at chiark.greenend.org.uk> wrote: > You've snipped the bit further on in that sentence where the OP > says that the file of interest is 2GB. Do you still want to try > mmap'ing it? Python's mmap object does not take an offset parameter. If it did, one could mmap smaller portions of the file.