:Matt,
:
:Does datasize limit the number of backed pages, or the amount of address
:space used by a process? I.e., can I grow myself a large chunk of address
:space using mmap to the same region of a file, and then read into that
:large chunk (presumably larger than the cache size if I want to be nasty)?
:If datasize only affects backed pages, then we can still do nasty large
:copies; if it affects address space, then nasty large copies are limited
:to the size of the writable address space (if using readv) or the size of
:the largest contiguous writable space (if using read).
:
: Robert N Watson
:
:rob...@fledge.watson.org http://www.watson.org/~robert/
:PGP key fingerprint: 03 01 DD 8E 15 67 48 73 25 6D 10 FC EC 68 C1 1C
The 'datasize' limit does not effect mmap(), only brk/sbrk. So,
in fact, I believe you can bypass the datasize limit by allocating
anonymous memory using mmap().
This is probably a bug. We should either limit the mmap()able space to
about the same size as the data segment limit, or keep track of the
amount of anonymous mapped memory and count that in the datasize
limit.
Matthew Dillon
<dil...@backplane.com>
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