The creation of a file of 5.25 GB took more than 30 min on "AMD64 Snow Leopard 3.x" buildbot, and so regrtest exited:
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[ 27/354] test_mmap
Thread 0x00007fff70439ca0:
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/test/test_mmap.py", line 685 in test_large_offset
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/case.py", line 387 in _executeTestPart
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/case.py", line 442 in run
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/case.py", line 494 in __call__
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/suite.py", line 105 in run
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/suite.py", line 67 in __call__
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/suite.py", line 105 in run
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/unittest/suite.py", line 67 in __call__
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/test/support.py", line 1078 in run
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/test/support.py", line 1166 in _run_suite
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/test/support.py", line 1192 in run_unittest
  File "/Users/pythonbuildbot/buildarea/3.x.hansen-osx-x86/build/Lib/test/test_mmap.py", line 706 in test_main
  File "./Lib/test/regrtest.py", line 1032 in runtest_inner
  File "./Lib/test/regrtest.py", line 826 in runtest
  File "./Lib/test/regrtest.py", line 650 in main
  File "./Lib/test/regrtest.py", line 1607 in <module>
make: *** [buildbottest] Error 1
program finished with exit code 2
elapsedTime=1909.711111
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http://www.python.org/dev/buildbot/all/builders/AMD64%20Snow%20Leopard%203.x/builds/46/steps/test/logs/stdio