V8 Buildbot: Remove swarming staging builders/testers.

masters/master.client.v8/slaves.cfg

 # -*- python -*-
 # ex: set syntax=python:
 
 # Copyright (c) 2012 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.
 
 # This is an list of dictionaries to describe slaves.
 # This list is intentionally flat to be easy to filter arbitrarily.
 
@@ skipping 22 matching lines @@
 
     # (Optional) VM datastore if a vm.
     #'vm_host_datastore': number,
 
     # (Optional) Random notes.
     #'notes': string,
   #},
   {
     'master': 'V8',
     'builder': ['V8 Linux - builder',
-                'V8 Linux - swarming staging builder',
                 'V8 Linux - debug builder'],
     'hostname': 'vm362-m3',
     'os': 'linux',
     'version': 'precise',
     'bits': '64',
   },
   {
     'master': 'V8',
     'builder': ['V8 Linux - nosnap builder',
                 'V8 Linux - nosnap debug builder',                
@@ skipping 130 matching lines @@
     'master': 'V8',
     'builder': ['V8 Linux64 TSAN',
                 'V8 Linux gcc 4.8'],
     'hostname': 'slave82-c3', # Fast VM.
     'os': 'linux',
     'version': 'trusty',
     'bits': '64',
   },
   {
     'master': 'V8',
-    'builder': ['V8 Linux64 - cfi', 'V8 Linux - swarming staging 3'],
+    'builder': ['V8 Linux64 - cfi', 'V8 Linux - swarming staging'],
     'hostname': 'slave80-c3',
     'os': 'linux',
     'version': 'precise',
     'bits': '64',
   },
   {
     'master': 'V8',
     'builder': ['V8 Linux - arm64 - sim - MSAN'],
     'hostname': 'slave30-c3',
     'os': 'linux',
@@ skipping 184 matching lines @@
       'V8 Mac64',
       'V8 Mac64 - debug',
       'V8 Mac64 - xcode',
     ],
     'hostname': 'vm%d-m3' % vm,
     'os': 'mac',
     'version': '10.6',
     'bits': '64',
   })
 
-for j in xrange(3):
-  slaves.append({
-    'master': 'V8',
-    'builder': ['V8 Linux - swarming staging 1',
-                'V8 Linux - swarming staging 2'],
-    'hostname': 'slave83-c3',
-    'os': 'linux',
-    'version': 'precise',
-    'bits': '64',
-    'subdir': str(j),
-  })
+def distribute_subdir_slaves(builders, hostnames):
+  """Distributes a list of builders to a list of hostnames with subdirs.
 
-# TODO(machenbach): Refactor usage of subdir slaves. Make it easier to
-# map builders to subdir slaves from a pool.
-slaves.append({
-  'master': 'V8',
-  'builder': ['V8 Arm'],
-  'hostname': 'slave83-c3',
-  'os': 'linux',
-  'version': 'precise',
-  'bits': '64',
-  'subdir': str(3),
-})
+  Each builder will be assigned to one (subdir) slave. The different hosts will
+  have an equal number (+/- 1) of subdir slaves.
 
-slaves.append({
-  'master': 'V8',
-  'builder': ['V8 Arm - debug'],
-  'hostname': 'slave83-c3',
-  'os': 'linux',
-  'version': 'precise',
-  'bits': '64',
-  'subdir': str(4),
-})
+  Example: Distributing builders [A, B, C, D, E] to slaves [X, Y] will result
+  in [AX0, BY0, CX1, DY1, EX2], where e.g. CX1 is builder C on host X with
+  subdir 1.
+  """
+  # Assuming there are more or equal builders than hostnames.

[tandrii(chromium), 2016/01/11 11:15:22]

I'd also sort builders and hostnames to make sure this is totally deterministic
and not dependent on inputs.

If say, someone calls this func with dict argument, it'd still work, but won't
be deterministic any more.

[Michael Achenbach, 2016/01/11 11:23:45]

Ensuring lists are used by another assert. I don't want to sort, as sorting
might change the distribution when adding new builders.

+  assert len(builders) >= len(hostnames)
 
-slaves.append({
-  'master': 'V8',
-  'builder': ['V8 Arm GC Stress'],
-  'hostname': 'slave83-c3',
-  'os': 'linux',
-  'version': 'precise',
-  'bits': '64',
-  'subdir': str(5),
-})
+  subdir_index = 0
+  hostname_index = 0
+  for builder in builders:
+    if hostname_index >= len(hostnames):
+      # All hostnames were used, rotate and advance the subdir index.
+      hostname_index = 0
+      subdir_index += 1
+    slaves.append({
+      'master': 'V8',
+      'builder': builder,
+      'hostname': hostnames[hostname_index],
+      'os': 'linux',
+      'version': 'precise',
+      'bits': '64',
+      'subdir': str(subdir_index),
+    })
+    hostname_index += 1
 
-slaves.append({
-  'master': 'V8',
-  'builder': ['V8 Win32'],
-  'hostname': 'slave83-c3',
-  'os': 'linux',
-  'version': 'precise',
-  'bits': '64',
-  'subdir': str(6),
-})
-
-slaves.append({
-  'master': 'V8',
-  'builder': ['V8 Win32 - debug'],
-  'hostname': 'slave83-c3',
-  'os': 'linux',
-  'version': 'precise',
-  'bits': '64',
-  'subdir': str(7),
-})
+distribute_subdir_slaves(
+  [
+    'V8 Arm',
+    'V8 Arm - debug',
+    'V8 Arm GC Stress',
+    'V8 Win32',
+    'V8 Win32 - debug',
+  ],
+  [
+    'slave83-c3',
+  ],
+)