5 files changed, 27 insertions, 25 deletions

diff --git a/command.py b/command.py
index ef2554da..7737ec71 100644
--- a/command.py
+++ b/command.py
@@ -23,6 +23,11 @@ from error import NoSuchProjectError
 from error import InvalidProjectGroupsError
 
 
+# How many jobs to run in parallel by default?  This assumes the jobs are
+# largely I/O bound and do not hit the network.
+DEFAULT_LOCAL_JOBS = min(os.cpu_count(), 8)
+
+
 class Command(object):
   """Base class for any command line action in repo.
   """
@@ -32,6 +37,10 @@ class Command(object):
   manifest = None
   _optparse = None
 
+  # Whether this command supports running in parallel.  If greater than 0,
+  # it is the number of parallel jobs to default to.
+  PARALLEL_JOBS = None
+
   def WantPager(self, _opt):
     return False
 
@@ -72,6 +81,11 @@ class Command(object):
   def _Options(self, p):
     """Initialize the option parser.
     """
+    if self.PARALLEL_JOBS is not None:
+      p.add_option(
+          '-j', '--jobs',
+          type=int, default=self.PARALLEL_JOBS,
+          help='number of jobs to run in parallel (default: %s)' % self.PARALLEL_JOBS)
 
   def _RegisteredEnvironmentOptions(self):
     """Get options that can be set from environment variables.
diff --git a/subcmds/branches.py b/subcmds/branches.py
index 20f51693..9665e85f 100644
--- a/subcmds/branches.py
+++ b/subcmds/branches.py
@@ -16,7 +16,7 @@ import itertools
 import multiprocessing
 import sys
 from color import Coloring
-from command import Command
+from command import Command, DEFAULT_LOCAL_JOBS
 
 # Number of projects to submit to a single worker process at a time.
 # This number represents a tradeoff between the overhead of IPC and finer
@@ -103,17 +103,7 @@ the branch appears in, or does not appear in.  If no project list
 is shown, then the branch appears in all projects.
 
 """
-
-  def _Options(self, p):
-    """Add flags to CLI parser for this subcommand."""
-    default_jobs = min(multiprocessing.cpu_count(), 8)
-    p.add_option(
-        '-j',
-        '--jobs',
-        type=int,
-        default=default_jobs,
-        help='Number of worker processes to spawn '
-        '(default: %s)' % default_jobs)
+  PARALLEL_JOBS = DEFAULT_LOCAL_JOBS
 
   def Execute(self, opt, args):
     projects = self.GetProjects(args)
diff --git a/subcmds/forall.py b/subcmds/forall.py
index ef11851b..d871b3ea 100644
--- a/subcmds/forall.py
+++ b/subcmds/forall.py
@@ -21,7 +21,7 @@ import sys
 import subprocess
 
 from color import Coloring
-from command import Command, MirrorSafeCommand
+from command import DEFAULT_LOCAL_JOBS, Command, MirrorSafeCommand
 import platform_utils
 
 _CAN_COLOR = [
@@ -113,8 +113,11 @@ terminal and are not redirected.
 If -e is used, when a command exits unsuccessfully, '%prog' will abort
 without iterating through the remaining projects.
 """
+  PARALLEL_JOBS = DEFAULT_LOCAL_JOBS
 
   def _Options(self, p):
+    super()._Options(p)
+
     def cmd(option, opt_str, value, parser):
       setattr(parser.values, option.dest, list(parser.rargs))
       while parser.rargs:
@@ -148,9 +151,6 @@ without iterating through the remaining projects.
     g.add_option('-v', '--verbose',
                  dest='verbose', action='store_true',
                  help='Show command error messages')
-    g.add_option('-j', '--jobs',
-                 dest='jobs', action='store', type='int', default=1,
-                 help='number of commands to execute simultaneously')
 
   def WantPager(self, opt):
     return opt.project_header and opt.jobs == 1
diff --git a/subcmds/status.py b/subcmds/status.py
index e293d75c..f0f2e034 100644
--- a/subcmds/status.py
+++ b/subcmds/status.py
@@ -17,7 +17,7 @@ import glob
 import multiprocessing
 import os
 
-from command import PagedCommand
+from command import DEFAULT_LOCAL_JOBS, PagedCommand
 
 from color import Coloring
 import platform_utils
@@ -76,11 +76,10 @@ the following meanings:
  d:  deleted       (    in index, not in work tree                )
 
 """
+  PARALLEL_JOBS = DEFAULT_LOCAL_JOBS
 
   def _Options(self, p):
-    p.add_option('-j', '--jobs',
-                 dest='jobs', action='store', type='int', default=2,
-                 help="number of projects to check simultaneously")
+    super()._Options(p)
     p.add_option('-o', '--orphans',
                  dest='orphans', action='store_true',
                  help="include objects in working directory outside of repo projects")
diff --git a/subcmds/sync.py b/subcmds/sync.py
index 5b1024df..18d2256e 100644
--- a/subcmds/sync.py
+++ b/subcmds/sync.py
@@ -177,12 +177,14 @@ If the remote SSH daemon is Gerrit Code Review, version 2.0.10 or
 later is required to fix a server side protocol bug.
 
 """
+  PARALLEL_JOBS = 1
 
   def _Options(self, p, show_smart=True):
     try:
-      self.jobs = self.manifest.default.sync_j
+      self.PARALLEL_JOBS = self.manifest.default.sync_j
     except ManifestParseError:
-      self.jobs = 1
+      pass
+    super()._Options(p)
 
     p.add_option('-f', '--force-broken',
                  dest='force_broken', action='store_true',
@@ -222,9 +224,6 @@ later is required to fix a server side protocol bug.
     p.add_option('-q', '--quiet',
                  dest='output_mode', action='store_false',
                  help='only show errors')
-    p.add_option('-j', '--jobs',
-                 dest='jobs', action='store', type='int',
-                 help="projects to fetch simultaneously (default %d)" % self.jobs)
     p.add_option('-m', '--manifest-name',
                  dest='manifest_name',
                  help='temporary manifest to use for this sync', metavar='NAME.xml')