.

zopenrace4.py

@@ -5,8 +5,10 @@
 from __future__ import print_function
 from ZODB import DB
 from ZODB.MappingStorage import MappingStorage
+from ZODB.POSException import ConflictError
 import transaction
 from persistent import Persistent
+from random import randint
 
 from golang import func, defer, select, default
 from golang import sync, context
@@ -67,6 +69,8 @@ def main():
     #
     # access to obj1 is organized to always trigger loading from zstor.
     # access to obj2 goes through zconn cache and so verifies whether the cache is not stale.
+    #
+    # XXX + commit
     @func
     def T1(ctx, name, N):
         db = dbopen()
@@ -88,18 +92,33 @@ def main():
             i1 = obj1.i
             i2 = obj2.i
             if i1 != i2:
-                raise AssertionError("T1: obj1.i (%d)  !=  obj2.i (%d)" % (i1, i2))
+                print('FAIL')
+                raise AssertionError("T%s: obj1.i (%d)  !=  obj2.i (%d)" % (name, i1, i2))
+
+            # change objects once in a while
+            if randint(0,4) == 0:
+                obj1.i += 1
+                obj2.i += 1
+
+            #transaction.abort() # we did not changed anything; also fails with commit
+            try:
+                transaction.commit()
+            except ConflictError:
+                #print('conflict -> ignore')
+                transaction.abort()
 
-            transaction.abort() # we did not changed anything; also fails with commit
             zconn.close()
 
         for i in range(N):
-            #print('T1%s.%d' % (name, i))
+            if ready(ctx.done()):
+                break
+            print('T1%s.%d' % (name, i))
             t1()
 
         raise RuntimeError("T1: done")
 
 
+    """
     # T2 changes obj1/obj2 in a loop by doing `objX.i += 1`.
     #
     # Since both objects start from 0, the invariant that `obj1.i == obj2.i` is always preserved.
@@ -127,6 +146,7 @@ def main():
                 break
             #print('T2.%d' % i)
             t2()
+    """
 
 
     # run T1 and T2 concurrently. As of 20191210, due to race condition in
@@ -135,9 +155,9 @@ def main():
 
     N = 100000
     wg = sync.WorkGroup(context.background())
-    for x in 'a':
+    for x in 'ab':
         wg.go(T1, x, N)
-    wg.go(T2, N)
+    #wg.go(T2, N)
     wg.wait()
 
     print('OK')