[Python-Dev] Memory woes under Windows

[Mark Hammond]

This is definately wierd!  As you only mentioned Win9x, I thought I would
give it a go on Win2k.

This is from a CVS update of only a few days ago, but it is a non-debug
build.  PII266 with 196MB ram:

         1 push       0.001
         2 push       0.000
         4 push       0.000
         8 push       0.000
        16 push       0.000
        32 push       0.000
        64 push       0.000
       128 push       0.001
       256 push       0.001
       512 push       0.003
      1024 push       0.006
      2048 push       0.011
      4096 push       0.040
      8192 push       0.043
     16384 push       0.103
     32768 push       0.203
     65536 push       0.583

Things are looking OK to here - the behaviour Tim expected.  But then
things seem to start going a little wrong:

    131072 push       1.456
    262144 push       4.763
    524288 push      16.119
   1048576 push      60.765

All of a sudden we seem to hit N*N behaviour?

I gave up waiting for the next one.  Performance monitor was showing CPU at
100%, but the Python process was only sitting on around 15MB of RAM (and
growing _very_ slowly - at the rate you would expect).  Machine had tons of
ram showing as available, and the disk was not thrashing - ie, Windows
definately had lots of mem available, and I have no reason to believe that
a malloc() would fail here - but certainly no one would ever want to wait
and see :-)

This was all definately built with MSVC6, SP3.

no-room-should-ever-have-more-than-one-windows-ly y'rs

Mark.