Remove caching of results by run_tests

SIGNIFICANTLY increases the performance of actually running tests...

2 files changed, 18 insertions, 113 deletions

diff --git a/tools/run_tests/jobset.py b/tools/run_tests/jobset.py
index d3259e724d..40409c4394 100755
--- a/tools/run_tests/jobset.py
+++ b/tools/run_tests/jobset.py
@@ -29,7 +29,6 @@
 
 """Run a group of subprocesses and then finish."""
 
-import hashlib
 import multiprocessing
 import os
 import platform
@@ -149,7 +148,7 @@ def which(filename):
 class JobSpec(object):
   """Specifies what to run for a job."""
 
-  def __init__(self, cmdline, shortname=None, environ=None, hash_targets=None,
+  def __init__(self, cmdline, shortname=None, environ=None,
                cwd=None, shell=False, timeout_seconds=5*60, flake_retries=0,
                timeout_retries=0, kill_handler=None, cpu_cost=1.0,
                verbose_success=False):
@@ -157,19 +156,14 @@ class JobSpec(object):
     Arguments:
       cmdline: a list of arguments to pass as the command line
       environ: a dictionary of environment variables to set in the child process
-      hash_targets: which files to include in the hash representing the jobs version
-                    (or empty, indicating the job should not be hashed)
       kill_handler: a handler that will be called whenever job.kill() is invoked
       cpu_cost: number of cores per second this job needs
     """
     if environ is None:
       environ = {}
-    if hash_targets is None:
-      hash_targets = []
     self.cmdline = cmdline
     self.environ = environ
     self.shortname = cmdline[0] if shortname is None else shortname
-    self.hash_targets = hash_targets or []
     self.cwd = cwd
     self.shell = shell
     self.timeout_seconds = timeout_seconds
@@ -180,7 +174,7 @@ class JobSpec(object):
     self.verbose_success = verbose_success
 
   def identity(self):
-    return '%r %r %r' % (self.cmdline, self.environ, self.hash_targets)
+    return '%r %r' % (self.cmdline, self.environ)
 
   def __hash__(self):
     return hash(self.identity())
@@ -205,9 +199,8 @@ class JobResult(object):
 class Job(object):
   """Manages one job."""
 
-  def __init__(self, spec, bin_hash, newline_on_success, travis, add_env):
+  def __init__(self, spec, newline_on_success, travis, add_env):
     self._spec = spec
-    self._bin_hash = bin_hash
     self._newline_on_success = newline_on_success
     self._travis = travis
     self._add_env = add_env.copy()
@@ -249,7 +242,7 @@ class Job(object):
       self._process = try_start()
     self._state = _RUNNING
 
-  def state(self, update_cache):
+  def state(self):
     """Poll current state of the job. Prints messages at completion."""
     def stdout(self=self):
       self._tempfile.seek(0)
@@ -293,8 +286,6 @@ class Job(object):
             stdout() if self._spec.verbose_success else None,
             do_newline=self._newline_on_success or self._travis)
         self.result.state = 'PASSED'
-        if self._bin_hash:
-          update_cache.finished(self._spec.identity(), self._bin_hash)
     elif (self._state == _RUNNING and
           self._spec.timeout_seconds is not None and
           time.time() - self._start > self._spec.timeout_seconds):
@@ -329,7 +320,7 @@ class Jobset(object):
   """Manages one run of jobs."""
 
   def __init__(self, check_cancelled, maxjobs, newline_on_success, travis,
-               stop_on_failure, add_env, cache):
+               stop_on_failure, add_env):
     self._running = set()
     self._check_cancelled = check_cancelled
     self._cancelled = False
@@ -338,9 +329,7 @@ class Jobset(object):
     self._maxjobs = maxjobs
     self._newline_on_success = newline_on_success
     self._travis = travis
-    self._cache = cache
     self._stop_on_failure = stop_on_failure
-    self._hashes = {}
     self._add_env = add_env
     self.resultset = {}
     self._remaining = None
@@ -367,37 +356,21 @@ class Jobset(object):
       if current_cpu_cost + spec.cpu_cost <= self._maxjobs: break
       self.reap()
     if self.cancelled(): return False
-    if spec.hash_targets:
-      if spec.identity() in self._hashes:
-        bin_hash = self._hashes[spec.identity()]
-      else:
-        bin_hash = hashlib.sha1()
-        for fn in spec.hash_targets:
-          with open(which(fn)) as f:
-            bin_hash.update(f.read())
-        bin_hash = bin_hash.hexdigest()
-        self._hashes[spec.identity()] = bin_hash
-      should_run = self._cache.should_run(spec.identity(), bin_hash)
-    else:
-      bin_hash = None
-      should_run = True
-    if should_run:
-      job = Job(spec,
-                bin_hash,
-                self._newline_on_success,
-                self._travis,
-                self._add_env)
-      self._running.add(job)
-      if not self.resultset.has_key(job.GetSpec().shortname):
-        self.resultset[job.GetSpec().shortname] = []
-    return True
+    job = Job(spec,
+              self._newline_on_success,
+              self._travis,
+              self._add_env)
+    self._running.add(job)
+    if not self.resultset.has_key(job.GetSpec().shortname):
+      self.resultset[job.GetSpec().shortname] = []
+      return True
 
   def reap(self):
     """Collect the dead jobs."""
     while self._running:
       dead = set()
       for job in self._running:
-        st = job.state(self._cache)
+        st = job.state()
         if st == _RUNNING: continue
         if st == _FAILURE or st == _KILLED:
           self._failures += 1
@@ -450,15 +423,6 @@ def _never_cancelled():
   return False
 
 
-# cache class that caches nothing
-class NoCache(object):
-  def should_run(self, cmdline, bin_hash):
-    return True
-
-  def finished(self, cmdline, bin_hash):
-    pass
-
-
 def tag_remaining(xs):
   staging = []
   for x in xs:
@@ -477,12 +441,10 @@ def run(cmdlines,
         travis=False,
         infinite_runs=False,
         stop_on_failure=False,
-        cache=None,
         add_env={}):
   js = Jobset(check_cancelled,
               maxjobs if maxjobs is not None else _DEFAULT_MAX_JOBS,
-              newline_on_success, travis, stop_on_failure, add_env,
-              cache if cache is not None else NoCache())
+              newline_on_success, travis, stop_on_failure, add_env)
   for cmdline, remaining in tag_remaining(cmdlines):
     if not js.start(cmdline):
       break
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index e4779e3a4e..c571a81eb2 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -33,7 +33,6 @@
 import argparse
 import ast
 import glob
-import hashlib
 import itertools
 import json
 import multiprocessing
@@ -78,24 +77,18 @@ class Config(object):
     if environ is None:
       environ = {}
     self.build_config = config
-    self.allow_hashing = (config != 'gcov')
     self.environ = environ
     self.environ['CONFIG'] = config
     self.tool_prefix = tool_prefix
     self.timeout_multiplier = timeout_multiplier
 
-  def job_spec(self, cmdline, hash_targets, timeout_seconds=5*60,
+  def job_spec(self, cmdline, timeout_seconds=5*60,
                shortname=None, environ={}, cpu_cost=1.0, flaky=False):
     """Construct a jobset.JobSpec for a test under this config
 
        Args:
          cmdline:      a list of strings specifying the command line the test
                        would like to run
-         hash_targets: either None (don't do caching of test results), or
-                       a list of strings specifying files to include in a
-                       binary hash to check if a test has changed
-                       -- if used, all artifacts needed to run the test must
-                          be listed
     """
     actual_environ = self.environ.copy()
     for k, v in environ.iteritems():
@@ -105,8 +98,6 @@ class Config(object):
                           environ=actual_environ,
                           cpu_cost=cpu_cost,
                           timeout_seconds=(self.timeout_multiplier * timeout_seconds if timeout_seconds else None),
-                          hash_targets=hash_targets
-                              if self.allow_hashing else None,
                           flake_retries=5 if flaky or args.allow_flakes else 0,
                           timeout_retries=3 if args.allow_flakes else 0)
 
@@ -425,7 +416,7 @@ class PythonLanguage(object):
     return []
 
   def build_steps(self):
-    return [['tools/run_tests/build_python.sh', tox_env] 
+    return [['tools/run_tests/build_python.sh', tox_env]
             for tox_env in self._tox_envs]
 
   def post_tests_steps(self):
@@ -1058,46 +1049,6 @@ runs_per_test = args.runs_per_test
 forever = args.forever
 
 
-class TestCache(object):
-  """Cache for running tests."""
-
-  def __init__(self, use_cache_results):
-    self._last_successful_run = {}
-    self._use_cache_results = use_cache_results
-    self._last_save = time.time()
-
-  def should_run(self, cmdline, bin_hash):
-    if cmdline not in self._last_successful_run:
-      return True
-    if self._last_successful_run[cmdline] != bin_hash:
-      return True
-    if not self._use_cache_results:
-      return True
-    return False
-
-  def finished(self, cmdline, bin_hash):
-    self._last_successful_run[cmdline] = bin_hash
-    if time.time() - self._last_save > 1:
-      self.save()
-
-  def dump(self):
-    return [{'cmdline': k, 'hash': v}
-            for k, v in self._last_successful_run.iteritems()]
-
-  def parse(self, exdump):
-    self._last_successful_run = dict((o['cmdline'], o['hash']) for o in exdump)
-
-  def save(self):
-    with open('.run_tests_cache', 'w') as f:
-      f.write(json.dumps(self.dump()))
-    self._last_save = time.time()
-
-  def maybe_load(self):
-    if os.path.exists('.run_tests_cache'):
-      with open('.run_tests_cache') as f:
-        self.parse(json.loads(f.read()))
-
-
 def _start_port_server(port_server_port):
   # check if a compatible port server is running
   # if incompatible (version mismatch) ==> start a new one
@@ -1217,7 +1168,7 @@ class BuildAndRunError(object):
 
 # returns a list of things that failed (or an empty list on success)
 def _build_and_run(
-    check_cancelled, newline_on_success, cache, xml_report=None, build_only=False):
+    check_cancelled, newline_on_success, xml_report=None, build_only=False):
   """Do one pass of building & running tests."""
   # build latest sequentially
   num_failures, resultset = jobset.run(
@@ -1266,7 +1217,6 @@ def _build_and_run(
         all_runs, check_cancelled, newline_on_success=newline_on_success,
         travis=args.travis, infinite_runs=infinite_runs, maxjobs=args.jobs,
         stop_on_failure=args.stop_on_failure,
-        cache=cache if not xml_report else None,
         add_env={'GRPC_TEST_PORT_SERVER': 'localhost:%d' % port_server_port})
     if resultset:
       for k, v in sorted(resultset.items()):
@@ -1295,14 +1245,9 @@ def _build_and_run(
   if num_test_failures:
     out.append(BuildAndRunError.TEST)
 
-  if cache: cache.save()
-
   return out
 
 
-test_cache = TestCache(runs_per_test == 1)
-test_cache.maybe_load()
-
 if forever:
   success = True
   while True:
@@ -1312,7 +1257,6 @@ if forever:
     previous_success = success
     errors = _build_and_run(check_cancelled=have_files_changed,
                             newline_on_success=False,
-                            cache=test_cache,
                             build_only=args.build_only) == 0
     if not previous_success and not errors:
       jobset.message('SUCCESS',
@@ -1324,7 +1268,6 @@ if forever:
 else:
   errors = _build_and_run(check_cancelled=lambda: False,
                           newline_on_success=args.newline_on_success,
-                          cache=test_cache,
                           xml_report=args.xml_report,
                           build_only=args.build_only)
   if not errors: