Currenlty, perftools keeps track of the cumulatively allocated memory, and dumps the
profile after every new gigabyte of cumulative memory allocated.

Sometimes it is useful to show only cumulative memory allocated by the certain point.
Or allocated between the particular time points.

I have the process that isn't high in allocated memory, but is high in cumulatively
allocated memory. (heap is low, but profiles are dumped a lot) So it allocates/frees
a lot while it works. This isn't expected, and perftools could help understand the
situation.

So, I suggest adding the separate environment variable:
CUMPROFILE=/tmp/cumulative

When such variable is set, perftools should write the /tmp/cumulative profile which
will be just like the heap profile, but instead of allocated memory will show cumulative
memory. In other words, heap profile is delta between cumulative profile and the aggregate
of all free operations performed.

This feature will allow some better insight into the process memory allocation.