[Zodb-checkins] CVS: ZODB3/ZEO - simul.py:1.12.8.2.18.13

[Tim Peters]

Update of /cvs-repository/ZODB3/ZEO
In directory cvs.zope.org:/tmp/cvs-serv13962/ZEO

Modified Files:
      Tag: Zope-2_6-branch
	simul.py 
Log Message:
Added UnboundedSimulation (-U), which never forgets or evicts anything.
No scheme can possibly do better than this, no matter how big its
cache.  For zope.org-main,

UnboundedSimulation, cache size [irrelevant]
  START TIME  DURATION    LOADS     HITS INVALS WRITES HITRATE  EVICTS
Nov 25 00:36   2:19:55    51340    19243    130    116   37.5%       0
Nov 25 02:56   1:55:01    54952    44369     66    442   80.7%       0
Nov 25 04:51   1:30:01    72530    64888    103     97   89.5%       0
Nov 25 06:21   1:00:13    46689    44533     33    111   95.4%       0
Nov 25 07:21   1:45:09    53628    50609    121    143   94.4%       0
Nov 25 09:06   1:15:02    58238    53737     51    163   92.3%       0
Nov 25 10:21   2:05:01   126466   115139    693   4751   91.0%       0
Nov 25 12:26   1:15:03    51919    50926     72     68   98.1%       0
Nov 25 13:41   2:45:03    69965    67569    608    296   96.6%       0
Nov 25 16:26   4:19:34    37131    34935      5     38   94.1%       0
Nov 25 20:46   6:05:06   110716   105092    324   2605   94.9%       0
Nov 26 02:51   2:04:57    79765    77765    837   1157   97.5%       0
Nov 26 04:56     40:01    53910    52593    140    187   97.6%       0
Nov 26 05:36   1:15:11    51677    50814     35    456   98.3%       0
Nov 26 06:51   1:00:08    51355    50782     49     92   98.9%       0
Nov 26 07:51   1:04:56    51923    50948     32     68   98.1%       0
Nov 26 08:56   1:05:13    66551    65701     33     90   98.7%       0
Nov 26 10:01     50:04    48137    47441     31     80   98.6%       0
Nov 26 10:51     28:00    40506    40199     30     70   99.2%       0
Nov 25 00:36  34:43:38  1177398  1087283   3393  11030   92.3%       0 OVERALL



=== ZODB3/ZEO/simul.py 1.12.8.2.18.12 => 1.12.8.2.18.13 ===
--- ZODB3/ZEO/simul.py:1.12.8.2.18.12	Thu Dec  4 22:29:14 2003
+++ ZODB3/ZEO/simul.py	Thu Dec  4 22:51:16 2003
@@ -47,7 +47,7 @@
     simclass = ZEOCacheSimulation
     theta = omicron = None
     try:
-        opts, args = getopt.getopt(sys.argv[1:], "bflyz2cOaTs:o:t:")
+        opts, args = getopt.getopt(sys.argv[1:], "bflyz2cOaTUs:o:t:")
     except getopt.error, msg:
         usage(msg)
         return 2
@@ -78,6 +78,8 @@
             simclass = ARCCacheSimulation
         if o == '-T':
             simclass = ThorSimulation
+        if o == '-U':
+            simclass = UnboundedSimulation
 
     if len(args) != 1:
         usage("exactly one file argument required")
@@ -1643,6 +1645,36 @@
             self.invals += 1
             self.total_invals += 1
             self._evict_without_bumping_evict_stats(obj)
+
+#############################################################################
+# Perfection:  What if the cache were unbounded, and never forgot anything?
+# This simulator answers that question directly; the cache size parameter
+# isn't used.
+
+class UnboundedSimulation(Simulation):
+
+    extraname = 'evicts'   # for some reason we *have* to define >= 1 extra
+
+    def __init__(self, cachelimit):
+        Simulation.__init__(self, cachelimit)
+        self.oids = Set()
+        self.evicts = self.total_evicts = 0
+
+    def write(self, oid, size):
+        self.oids.add(oid)
+
+    def load(self, oid, size):
+        if oid in self.oids:
+            self.hits += 1
+            self.total_hits += 1
+        else:
+            self.oids.add(oid)
+
+    def inval(self, oid):
+        if oid in self.oids:
+            self.invals += 1
+            self.total_invals += 1
+            self.oids.remove(oid)
 
 if __name__ == "__main__":
     sys.exit(main())