[Piuparts-commits] [SCM] piuparts git repository branch, develop, updated. 0.49-99-g9bcbbe2

[Andreas Beckmann]

The following commit has been merged in the develop branch:
commit 9bcbbe21782162d30517cd019b8d7b855b40e07e
Author: Andreas Beckmann <anbe at debian.org>
Date:   Tue Feb 5 16:14:13 2013 +0100

    p-s: check load frequently and sleep if it exceeds threshold
    
    tunable via [global] slave-load-max = 1.5
    0 (default) disables
    9.5 seems to be reasonable for 8 slaves running on 4 cores / 8 threads
    
    Signed-off-by: Andreas Beckmann <anbe at debian.org>

diff --git a/README.txt b/README.txt
index d3cf224..1a3d640 100644
--- a/README.txt
+++ b/README.txt
@@ -489,6 +489,11 @@ used for all further sections.
 * "doc-root" is the location where the webserver will serve the
  piuparts report from. Default: "/".
 
+* "slave-load-max" specifies the system load limit when
+ piuparts-slave will enter sleep mode. Operation will be resumed
+ after load drops below 'slave-load-max - 1.0'. Floating point
+ value. Defaults to 0 (= disabled).
+
 ==== section specific configuration
 
 The section specific settings will be reloaded each time a section
diff --git a/debian/changelog b/debian/changelog
index 7153fd8..49e4763 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -19,6 +19,7 @@ piuparts (0.50) UNRELEASED; urgency=low
       + known-problem-directory (for known_problem definitions)
       + backup-directory (for the master script prepare_backup)
       + PYTHONPATH (to find the python modules in non-default path setups)
+      + slave-load-max
     - Setting tmpdir is now mandatory for master/slave operation.
   * piupartslib/conf.py:
   * piupartslib/packagesdb.py:
@@ -32,6 +33,10 @@ piuparts (0.50) UNRELEASED; urgency=low
     - Fix SIGHUP handling while recycling.
     - Flush and unreserve all sections on interrupt.
     - Add support for running piuparts under /usr/bin/timeout.
+    - Check system load frequently and enter sleep mode if threshold
+      (piuparts.conf global setting slave-load-max) is exceeded. Operation
+      will be resumed after load drops below 'slave-load-max - 1.0'. Disabled
+      by default.
   * piuparts-analyze.py:
     - Add support for magic "$DISTRO/None" versions.
   * piuparts-report.py:
diff --git a/piuparts-slave.py b/piuparts-slave.py
index 5445920..7d2d9d6 100644
--- a/piuparts-slave.py
+++ b/piuparts-slave.py
@@ -90,6 +90,7 @@ class Config(piupartslib.conf.Config):
                 "keep-sources-list": "no",
                 "arch": None,
                 "precedence": "1",
+                "slave-load-max": None,
             },
             defaults_section=defaults_section)
 
@@ -337,6 +338,35 @@ class Section:
 
         self._slave = Slave()
 
+
+    def _throttle_if_overloaded(self):
+        global interrupted
+        if interrupted or got_sighup:
+            return
+        if self._config["slave-load-max"] is None:
+            return
+        load_max = float(self._config["slave-load-max"])
+        if load_max < 1.0:
+            return
+        if os.getloadavg()[0] <= load_max:
+            return
+        load_resume = max(load_max - 1.0, 0.9)
+        secs = random.randrange(30, 90)
+        while True:
+            load = os.getloadavg()[0]
+            if load <= load_resume:
+                break
+            logging.info("Sleeping due to high load (%.2f)" % load)
+            try:
+                time.sleep(secs)
+            except KeyboardInterrupt:
+                interrupted = True
+            if interrupted or got_sighup:
+                break
+            if secs < 300:
+                secs += random.randrange(30, 90)
+
+
     def _connect_to_master(self, recycle=False):
         self._slave.set_master_host(self._config["master-host"])
         self._slave.set_master_user(self._config["master-user"])
@@ -386,6 +416,8 @@ class Section:
         if time.time() < self.sleep_until(recycle=recycle):
             return 0
 
+        self._throttle_if_overloaded()
+
         if interrupted or got_sighup:
             do_processing = False
 
@@ -534,13 +566,12 @@ class Section:
         test_count = 0
         self._check_tarball()
         for package_name, version in self._slave.get_reserved():
-            if got_sighup:
+            self._throttle_if_overloaded()
+            if interrupted or got_sighup:
                 break
             test_count += 1
             test_package(self._config, package_name, version, packages_files)
             self._slave.forget_reserved(package_name, version)
-            if interrupted:
-                break
         self._talk_to_master(unreserve=interrupted)
         return test_count
 

-- 
piuparts git repository