tools: allows heapwatch to enable mutex and blocking profiles

test/heapwatch/heapWatch.py

@@ -159,6 +159,32 @@ def get_pprof_snapshot(self, name, snapshot_name=None, outdir=None, timeout=None
         logger.debug('%s -> %s', self.nick, outpath)
         return outpath
 
+    def get_debug_settings_pprof(self):
+        timeout = self.timeout
+        url = 'http://' + self.net + '/debug/settings/pprof'
+        headers = self.headers.copy()
+        headers['X-Algo-API-Token'] = self.admin_token
+        try:
+            response = urllib.request.urlopen(urllib.request.Request(url, headers=headers), timeout=timeout)
+        except Exception as e:
+            logger.error('could not fetch %s from %s via %r (%s)', '/debug/settings/pprof', self.path, url, e)
+            return
+        blob = response.read()
+        return json.loads(blob)
+
+    def set_debug_settings_pprof(self, settings):
+        timeout = self.timeout
+        url = 'http://' + self.net + '/debug/settings/pprof'
+        headers = self.headers.copy()
+        headers['X-Algo-API-Token'] = self.admin_token
+        data = json.dumps(settings).encode()
+        try:
+            response = urllib.request.urlopen(urllib.request.Request(url, data=data, headers=headers, method='PUT'), timeout=timeout)
+        except Exception as e:
+            logger.error('could not put %s to %s via %r (%s)', settings, self.path, url, e)
+            return
+        response.close()
+
     def get_heap_snapshot(self, snapshot_name=None, outdir=None):
         return self.get_pprof_snapshot('heap', snapshot_name, outdir)
 
@@ -355,6 +381,24 @@ def do_snap(self, now, get_cpu=False, fraction=False):
                 rss, vsz = rssvsz
                 with open(os.path.join(self.args.out, nick + '.heap.csv'), 'at') as fout:
                     fout.write('{},{},{},{}\n'.format(snapshot_name,snapshot_isotime,rss, vsz))
+        if self.args.mutex or self.args.block:
+            # get mutex/blocking profiles state and enable as needed
+            for ad in self.they:
+                settings = ad.get_debug_settings_pprof()
+                updated = False
+                if self.args.mutex:
+                    mrate = settings.get('mutex-rate', 0)
+                    if mrate == 0:
+                        settings['mutex-rate'] = 5  # 1/5 of events recorded
+                        updated = True
+                if self.args.block:
+                    brate = settings.get('block-rate', 0)
+                    if brate == 0:
+                        settings['block-rate'] = 100 # one blocking event per 100 nanoseconds spent blocked.
+                        updated = True
+                if updated:
+                    logger.debug('enabling mutex/blocking profiles on %s', ad.path)
+                    ad.set_debug_settings_pprof(settings)
         if self.args.goroutine:
             for ad in self.they:
                 ad.get_goroutine_snapshot(snapshot_name, outdir=self.args.out)
@@ -466,12 +510,6 @@ def main():
     else:
         logging.basicConfig(level=logging.INFO)
 
-    if args.block:
-        print('Ensure algod is compiled with `runtime.SetBlockProfileRate()` set')
-
-    if args.mutex:
-        print('Ensure algod is compiled with `runtime.SetMutexProfileFraction()` set')
-
     for nre in args.tf_name_re:
         try:
             # do re.compile just to check