[project @ 2001-11-26 16:54:21 by simonmar]
Profiling cleanup. This commit eliminates some duplication in the various heap profiling subsystems, and generally centralises much of the machinery. The key concept is the separation of a heap *census* (which is now done in one place only instead of three) from the calculation of retainer sets. Previously the retainer profiling code also did a heap census on the fly, and lag-drag-void profiling had its own census machinery. Value-adds: - you can now restrict a heap profile to certain retainer sets, but still display by cost centre (or type, or closure or whatever). - I've added an option to restrict the maximum retainer set size (+RTS -R<size>, defaulting to 8). - I've cleaned up the heap profiling options at the request of Simon PJ. See the help text for details. The new scheme is backwards compatible with the old. - I've removed some odd bits of LDV or retainer profiling-specific code from various parts of the system. - the time taken doing heap censuses (and retainer set calculation) is now accurately reported by the RTS when you say +RTS -Sstderr. Still to come: - restricting a profile to a particular biography (lag/drag/void/use). This requires keeping old heap censuses around, but the infrastructure is now in place to do this.