Kill builds that produce too much output

third_party/buildbot_slave_8_4/README.chromium

Index: third_party/buildbot_slave_8_4/README.chromium
diff --git a/third_party/buildbot_slave_8_4/README.chromium b/third_party/buildbot_slave_8_4/README.chromium
index de91dc1d6e032631620981010d3c8d762d28409c..91eee6726c755fd22f9ac7f6fa44857a39d91a27 100644
--- a/third_party/buildbot_slave_8_4/README.chromium
+++ b/third_party/buildbot_slave_8_4/README.chromium
@@ -80,3 +80,36 @@ index 75d6cc4..6a96b03 100644
 +        # never called. In testing mode, Reboot() returns immediately
 +        # with no effect, and we need to recover.
          self.failed(RuntimeError("SIGKILL failed to kill process"))
+
+diff --git a/third_party/buildbot_slave_8_4/buildslave/runprocess.py b/third_party/buildbot_slave_8_4/buildslave/runprocess.py
+index 6a96b03..1b79a17 100644
+--- a/third_party/buildbot_slave_8_4/buildslave/runprocess.py
++++ b/third_party/buildbot_slave_8_4/buildslave/runprocess.py
+@@ -212,6 +212,7 @@ class RunProcess:
+     BACKUP_TIMEOUT = 5
+     KILL = "KILL"
+     CHUNK_LIMIT = 128*1024
++    OUTPUT_LIMIT = 50*1024*1024
+ 
+     # Don't send any data until at least BUFFER_SIZE bytes have been collected
+     # or BUFFER_TIMEOUT elapsed
+@@ -322,6 +323,7 @@ class RunProcess:
+         self.buffered = deque()
+         self.buflen = 0
+         self.buftimer = None
++        self.totalOutputLength = 0
+ 
+         if usePTY == "slave-config":
+             self.usePTY = self.builder.usePTY
+@@ -621,6 +623,11 @@ class RunProcess:
+         """
+         n = len(data)
+ 
++        self.totalOutputLength += n
++        if self.totalOutputLength > self.OUTPUT_LIMIT:
++            self.kill('output limit (%d) exceeded' % self.OUTPUT_LIMIT)
++            return
++
+         self.buflen += n
+         self.buffered.append((logname, data))
+         if self.buflen > self.BUFFER_SIZE: