@@ -73,7 +73,7 @@ static TransactionId DtmGetNextXid(void);
7373static TransactionId DtmGetNewTransactionId (bool isSubXact );
7474static TransactionId DtmGetOldestXmin (Relation rel ,bool ignoreVacuum );
7575
76- static bool TransactionIdIsInDtmSnapshot (TransactionId xid );
76+ static bool TransactionIdIsInSnapshot (TransactionId xid , Snapshot snapshot );
7777static bool TransactionIdIsInDoubt (TransactionId xid );
7878
7979static void dtm_shmem_startup (void );
@@ -119,18 +119,18 @@ static void DumpSnapshot(Snapshot s, char *name)
119119XTM_INFO ("%s\n" ,buf );
120120}
121121
122- static bool TransactionIdIsInDtmSnapshot (TransactionId xid )
122+ static bool TransactionIdIsInSnapshot (TransactionId xid , Snapshot snapshot )
123123{
124- return xid >=DtmSnapshot . xmax
125- || bsearch (& xid ,DtmSnapshot . xip ,DtmSnapshot . xcnt ,sizeof (TransactionId ),xidComparator )!= NULL ;
124+ return xid >=snapshot -> xmax
125+ || bsearch (& xid ,snapshot -> xip ,snapshot -> xcnt ,sizeof (TransactionId ),xidComparator )!= NULL ;
126126}
127127
128128
129129static bool TransactionIdIsInDoubt (TransactionId xid )
130130{
131131bool inDoubt ;
132132
133- if (!TransactionIdIsInDtmSnapshot (xid )) {
133+ if (!TransactionIdIsInSnapshot (xid , & DtmSnapshot )) {
134134LWLockAcquire (dtm -> hashLock ,LW_SHARED );
135135inDoubt = hash_search (xid_in_doubt ,& xid ,HASH_FIND ,NULL )!= NULL ;
136136LWLockRelease (dtm -> hashLock );
@@ -175,8 +175,23 @@ static void DtmMergeSnapshots(Snapshot dst, Snapshot src)
175175
176176static void DtmMergeWithActiveSnapshot (Snapshot dst )
177177{
178+ int i ,j ;
179+ XLogRecPtr lsn ;
180+ Snapshot src = & dtm -> activeSnapshot ;
181+
178182LWLockAcquire (dtm -> xidLock ,LW_EXCLUSIVE );
179- DtmMergeSnapshots (dst ,& dtm -> activeSnapshot );
183+ for (i = 0 ,j = 0 ;i < src -> xcnt ;i ++ ) {
184+ if (!TransactionIdIsInSnapshot (src -> xip [i ],dst )
185+ && DtmGetTransactionStatus (src -> xip [i ],& lsn )== TRANSACTION_STATUS_IN_PROGRESS )
186+ {
187+ src -> xip [j ++ ]= src -> xip [i ];
188+ }
189+ }
190+ src -> xcnt = j ;
191+ if (j != 0 ) {
192+ src -> xmin = src -> xip [0 ];
193+ DtmMergeSnapshots (dst ,src );
194+ }
180195LWLockRelease (dtm -> xidLock );
181196}
182197