The result of SF patch #1471578: big-memory tests for strings, lists and

tuples. Lots to be added, still, but this will give big-memory people
something to play with in 2.5 alpha 2, and hopefully get more people to
write these tests.

Lib/test/regrtest.py

@@ -25,6 +25,7 @@ Command line options:
 -N: nocoverdir -- Put coverage files alongside modules
 -L: runleaks   -- run the leaks(1) command just before exit
 -R: huntrleaks -- search for reference leaks (needs debug build, v. slow)
+-M: memlimit   -- run very large memory-consuming tests
 
 If non-option arguments are present, they are names for tests to run,
 unless -x is given, in which case they are names for tests not to run.
@@ -63,6 +64,19 @@ of times further it is run and 'fname' is the name of the file the
 reports are written to.  These parameters all have defaults (5, 4 and
 "reflog.txt" respectively), so the minimal invocation is '-R ::'.
 
+-M runs tests that require an exorbitant amount of memory. These tests
+typically try to ascertain containers keep working when containing more than
+2 bilion objects, and only work on 64-bit systems. The passed-in memlimit,
+which is a string in the form of '2.5Gb', determines howmuch memory the
+tests will limit themselves to (but they may go slightly over.) The number
+shouldn't be more memory than the machine has (including swap memory). You
+should also keep in mind that swap memory is generally much, much slower
+than RAM, and setting memlimit to all available RAM or higher will heavily
+tax the machine. On the other hand, it is no use running these tests with a
+limit of less than 2.5Gb, and many require more than 20Gb. Tests that expect
+to use more than memlimit memory will be skipped. The big-memory tests
+generally run very, very long.
+
 -u is used to specify which special resource intensive tests to run,
 such as those requiring large file support or network connectivity.
 The argument is a comma-separated list of words indicating the
@@ -180,12 +194,12 @@ def main(tests=None, testdir=None, verbose=0, quiet=False, generate=False,
 
     test_support.record_original_stdout(sys.stdout)
     try:
-        opts, args = getopt.getopt(sys.argv[1:], 'hvgqxsrf:lu:t:TD:NLR:w',
+        opts, args = getopt.getopt(sys.argv[1:], 'hvgqxsrf:lu:t:TD:NLR:wM:',
                                    ['help', 'verbose', 'quiet', 'generate',
                                     'exclude', 'single', 'random', 'fromfile',
                                     'findleaks', 'use=', 'threshold=', 'trace',
                                     'coverdir=', 'nocoverdir', 'runleaks',
-                                    'huntrleaks=', 'verbose2',
+                                    'huntrleaks=', 'verbose2', 'memlimit=',
                                     ])
     except getopt.error, msg:
         usage(2, msg)
@@ -241,6 +255,8 @@ def main(tests=None, testdir=None, verbose=0, quiet=False, generate=False,
                 huntrleaks[1] = int(huntrleaks[1])
             if len(huntrleaks[2]) == 0:
                 huntrleaks[2] = "reflog.txt"
+        elif o in ('-M', '--memlimit'):
+            test_support.set_memlimit(a)
         elif o in ('-u', '--use'):
             u = [x.lower() for x in a.split(',')]
             for r in u: