🚀 go-pugleaf

In article <43qh32INN3hl@keats.ugrad.cs.ubc.ca>, c2a192@ugrad.cs.ubc.ca (Kazimir Kylheku) writes:

  Kazimir> Once you allocate a certain number of pages which are made
  Kazimir> to appear as a linear block, you still face the possiblity
  Kazimir> of wastefully fragmenting the space. The underlying VM
  Kazimir> system doesn't know about your used and unused areas.
  Kazimir> Library functions like malloc() will typically _not_ free a
  Kazimir> frame of memory that is completely within an allocation
  Kazimir> chunk that has just been freed.

I think this is mostly (perhaps only ;-) ) because UNIX systems do not
typically let you "unallocate" a page totally within the process'
virtual memory space (no function is provided that does so).  The only
function available to manipulate memory is sbrk(), which can request
more (or sometime? return) memory at the end of the current process vm
space.  The GNU allocator, for example, will return to the system
pages of vm at the end of the heap, if all allocated blocks within
those pages are freed.

Moises
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