.

go/zodb/connection.go

@@ -113,7 +113,8 @@ type LiveCache struct {
 	// Hopefully we don't have cycles with BTree/Bucket.
 
 	sync.Mutex
-	objtab map[Oid]*weak.Ref // oid -> weak.Ref(IPersistent)
+	objtab map[Oid]*weak.Ref   // oid -> weak.Ref(IPersistent); potentially have a referee
+	pinned map[Oid]IPersistent // objects that are pinned and don't have any referee currently
 
 	// hooks for application to influence live caching decisions.
 	control LiveCacheControl
@@ -169,6 +170,7 @@ func newConnection(db *DB, at Tid) *Connection {
 		at:    at,
 		cache: LiveCache{
 			objtab: make(map[Oid]*weak.Ref),
+			pinned: make(map[Oid]IPersistent),
 		},
 	}
 }
@@ -204,12 +206,40 @@ func (cache *LiveCache) Get(oid Oid) IPersistent {
 			obj = xobj.(IPersistent)
 		}
 	}
+	if obj == nil {
+		obj = cache.pinned[oid]
+		// XXX -> weakref?
+		// XXX -> start lookup from pinned?
+	}
 	return obj
 }
 
-// set sets objects corresponding ... XXX
+// set sets objects corresponding to oid.
 func (cache *LiveCache) set(oid Oid, obj IPersistent) {
+	var pc PCachePolicy // XXX -> cp, pol? ... ?
+	if cc := cache.control; cc != nil {
+		pc = cache.control.PCacheClassify(obj)
+	}
+	// XXX remember pc in obj .pcachePolicy?
+	// XXX del .objtab[oid] ?
+	// XXX del .pinned[oid] ?
+	if pc & PCachePinObject != 0 {
+		cache.pinned[oid] = obj
+	} else {
 		cache.objtab[oid] = weak.NewRef(obj)
+	}
+}
+
+// forEach calls f for all objects in the cache.
+func (cache *LiveCache) forEach(f func(IPersistent)) {
+	for _, obj := range cache.pinned {
+		f(obj)
+	}
+	for _, wobj := range cache.objtab {
+		if xobj := wobj.Get(); xobj != nil {
+			f(xobj.(IPersistent))
+		}
+	}
 }
 
 // SetControl installs c to handle cache decisions.
@@ -220,6 +250,7 @@ func (cache *LiveCache) set(oid Oid, obj IPersistent) {
 // It is not safe to call SetControl simultaneously to other cache operations.
 func (cache *LiveCache) SetControl(c LiveCacheControl) {
 	cache.control = c
+	// XXX reclassify all objects
 }
 
 // get is like Get, but used when we already know object class.
@@ -232,7 +263,7 @@ func (conn *Connection) get(class string, oid Oid) (IPersistent, error) {
 	obj := conn.cache.Get(oid)
 	if obj == nil {
 		obj = newGhost(class, oid, conn)
-		conn.cache.objtab[oid] = weak.NewRef(obj) // XXX -> conn.cache.set(oid, obj)
+		conn.cache.set(oid, obj)
 		checkClass = false
 	}
 	conn.cache.Unlock()

go/zodb/db.go

@@ -565,14 +565,9 @@ func (conn *Connection) resync1(at Tid) {
 	defer conn.cache.Unlock()
 
 	if δall {
-		// XXX keep synced with LiveCache details
-		// XXX -> conn.cache.forEach?
-		for _, wobj := range conn.cache.objtab {
-			obj, _ := wobj.Get().(IPersistent)
-			if obj != nil {
+		conn.cache.forEach(func(obj IPersistent) {
 			obj.PInvalidate()
-			}
-		}
+		})
 	} else {
 		for oid := range δobj {
 			obj := conn.cache.Get(oid)

go/zodb/persistent_test.go

@@ -384,7 +384,7 @@ func (t *tPersistentConn) checkObj(obj *MyObject, oid Oid, serial Tid, state Obj
 	connObj := cache.Get(oid)
 	cache.Unlock()
 	if obj != connObj {
-		t.Fatalf("cache.get %s -> not same object:\nhave: %#v\nwant: %#v", oid, connObj, oid)
+		t.Fatalf("cache.get %s -> not same object:\nhave: %#v\nwant: %#v", oid, connObj, obj)
 	}
 
 	// and conn.Get must return exactly obj.
@@ -393,7 +393,7 @@ func (t *tPersistentConn) checkObj(obj *MyObject, oid Oid, serial Tid, state Obj
 		t.Fatal(err)
 	}
 	if obj != connObj {
-		t.Fatalf("conn.get %s -> not same object:\nhave: %#v\nwant: %#v", oid, connObj, oid)
+		t.Fatalf("conn.get %s -> not same object:\nhave: %#v\nwant: %#v", oid, connObj, obj)
 	}
 
 	checkObj(t.T, obj, t.conn, oid, serial, state, refcnt)
@@ -788,11 +788,11 @@ func TestLiveCache(t0 *testing.T) {
 	assert.NotEqual(xobj2, nil)
 	assert.NotEqual(xobj3, nil)
 	obj2 = xobj2.(*MyObject)
-	obj3 = xobj2.(*MyObject)
+	obj3 = xobj3.(*MyObject)
 	t.checkObj(obj2, 102, at1, UPTODATE,      0, "труд")
 	t.checkObj(obj3, 103, InvalidTid, GHOST,  0)
 
-	assert.Equal(obj2._v_cookie, "zzz")	// XXX labour
+	assert.Equal(obj2._v_cookie, "labour")
 	assert.Equal(obj3._v_cookie, "may")
 
 	obj1 = t.Get(101)