gclient: exponential backoff of SCM commands on known failure types....

scm.py

 # Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """SCM-specific utility classes."""
 
 import cStringIO
 import glob
 import os
 import re
@@ skipping 346 matching lines @@
     # else, which is good.  Note that the patterns are only effective when
     # these commands are used in their ordinary forms, the patterns are invalid
     # for "svn status --show-updates", for example.
     pattern = {
           'checkout': update_pattern,
           'status':   status_pattern,
           'update':   update_pattern,
         }[args[0]]
     compiled_pattern = re.compile(pattern)
     # Place an upper limit.
+    backoff_time = 5
     for _ in range(10):
       previous_list_len = len(file_list)
       failure = []
 
       def CaptureMatchingLines(line):
         match = compiled_pattern.search(line)
         if match:
           file_list.append(match.group(1))
         if line.startswith('svn: '):
           failure.append(line)
@@ skipping 33 matching lines @@
           else:
             # Progress was made, convert to update since an aborted checkout
             # is now an update.
             args = ['update'] + args[1:]
         else:
           # It was an update or export.
           # We enforce that some progress has been made or a known failure.
           if len(file_list) == previous_list_len and not IsKnownFailure():
             # No known svn error was found and no progress, bail out.
             raise
-        print "Sleeping 15 seconds and retrying...."
-        time.sleep(15)
+        print "Sleeping %.1f seconds and retrying...." % backoff_time
+        time.sleep(backoff_time)
+        backoff_time *= 1.3
         continue
       break
 
   @staticmethod
   def CaptureInfo(relpath, in_directory=None, print_error=True):
     """Returns a dictionary from the svn info output for the given file.
 
     Args:
       relpath: The directory where the working copy resides relative to
         the directory given by in_directory.
@@ skipping 410 matching lines @@
     if not SVN.current_version:
       SVN.current_version = SVN.Capture(['--version']).split()[2]
     current_version_list = map(only_int, SVN.current_version.split('.'))
     for min_ver in map(int, min_version.split('.')):
       ver = current_version_list.pop(0)
       if ver < min_ver:
         return (False, SVN.current_version)
       elif ver > min_ver:
         return (True, SVN.current_version)
     return (True, SVN.current_version)