Re: [MIT-Scheme-devel] profiling and bugs in stack parser

[Taylor R Campbell]

   Date: Thu, 10 Dec 2009 08:36:47 -0800
   From: Joe Marshall <address@hidden>

   You should run it past Michael Blair.  If I understand correctly, he was
   also doing statistical profiling and had run into either than exact same
   problem or something much similar where it was difficult to impossible
   for the system to really determine what state it was in.

That's a little different.  Ziggy's profiler works at the much lower
level of trying to figure out what's happening the moment the process
is interrupted by an operating system signal -- this requires guessing
at what kind of code the machine's interrupted PC is in, what the
state of the stack might be, &c.  My profiler works by registering
timer events at the Scheme level, which are run only when the system
is in a nice Schemely state which CWCC can reify, and the problem is
just that it runs into a bug in the stack parser.