RE: how to determine a programs memory usage at runtime?
On 21 June 2004 09:14, John Meacham wrote:
There might be some RTS calls to query the heap, but someone else is probably more qualified to comment on that.
The value of the mblocks_allocated variable in the RTS will give you the number of "megablocks" currently mmap()ed into the address space of the executable, which roughly equates to the amount of memory the program is using. A megablock is MBLOCK_SIZE bytes, currently 1Mb. Megablocks are never released, so this only gives you an upper limit for the amount of memory in use. Cheers, Simon
On Mon, Jun 21, 2004 at 02:50:39PM +0100, Simon Marlow wrote:
On 21 June 2004 09:14, John Meacham wrote:
There might be some RTS calls to query the heap, but someone else is probably more qualified to comment on that.
The value of the mblocks_allocated variable in the RTS will give you the number of "megablocks" currently mmap()ed into the address space of the executable, which roughly equates to the amount of memory the program is using. A megablock is MBLOCK_SIZE bytes, currently 1Mb.
Megablocks are never released, so this only gives you an upper limit for the amount of memory in use.
Thanks John and Simon, The mblocks_allocated variable should give me what I want. I think having access to this would also be useful to people who are profiling their programs. You see a few papers where people want to report how much memory their application needs, and having a high-water mark is usually good enough. Beats trying to get the information from top. Cheers, Bernie.
participants (2)
-
Bernard James POPE -
Simon Marlow