Use window for snapshots in DTMD

knizhnik · knizhnik · commit fcd31f355a8b · 2015-09-18T12:48:05.000+03:00
diff --git a/contrib/pg_xtm/dtmd/src/main.c b/contrib/pg_xtm/dtmd/src/main.c
@@ -332,9 +332,8 @@ static void gen_snapshot(Snapshot *s, int node) {
 
 static void gen_snapshots(GlobalTransaction *gt) {
 	int n;
-    assert(gt->n_snapshots < MAX_SNAPSHOTS_PER_TRANS);
 	for (n = 0; n < MAX_NODES; n++) {
-		gen_snapshot(&gt->participants[n].snapshot[gt->n_snapshots], n);
+		gen_snapshot(&gt->participants[n].snapshot[gt->n_snapshots % MAX_SNAPSHOTS_PER_TRANS], n);
 	}
     gt->n_snapshots += 1;
 }
@@ -380,7 +379,7 @@ static char *onsnapshot(void *stream, void *clientdata, cmd_t *cmd) {
 	}
 	assert(t->snapshot_no < gt->n_snapshots);
 
-	return snapshot_serialize(&t->snapshot[t->snapshot_no++]);
+	return snapshot_serialize(&t->snapshot[t->snapshot_no++ % MAX_SNAPSHOTS_PER_TRANS]);
 }
 
 static bool queue_for_transaction_finish(void *stream, void *clientdata, int node, xid_t xid, char cmd) {
diff --git a/contrib/pg_xtm/pg_dtm.c b/contrib/pg_xtm/pg_dtm.c
@@ -68,12 +68,13 @@ static void DtmEnsureConnection(void)
     XTM_TRACE("XTM: DtmEnsureConnection\n");
     while (attempt < XTM_CONNECT_ATTEMPTS) { 
         if (DtmConn) {
-            break;
+            return;
         }
         XTM_TRACE("XTM: DtmEnsureConnection, attempt #%u\n", attempt);
         DtmConn = DtmConnect("127.0.0.1", 5431);
         attempt++;
     }
+    elog(ERROR, "Failed to connect to DTMD");
 }
 
 static void DumpSnapshot(Snapshot s, char *name)

Original file line number	Diff line number	Diff line change
`@@ -332,9 +332,8 @@ static void gen_snapshot(Snapshot *s, int node) {`
`332`	`332`
`333`	`333`	`static void gen_snapshots(GlobalTransaction *gt) {`
`334`	`334`	`int n;`
`335`		`- assert(gt->n_snapshots < MAX_SNAPSHOTS_PER_TRANS);`
`336`	`335`	`for (n = 0; n < MAX_NODES; n++) {`
`337`		`- gen_snapshot(&gt->participants[n].snapshot[gt->n_snapshots], n);`
	`336`	`+ gen_snapshot(&gt->participants[n].snapshot[gt->n_snapshots % MAX_SNAPSHOTS_PER_TRANS], n);`
`338`	`337`	`}`
`339`	`338`	`gt->n_snapshots += 1;`
`340`	`339`	`}`
`@@ -380,7 +379,7 @@ static char onsnapshot(void stream, void clientdata, cmd_t cmd) {`
`380`	`379`	`}`
`381`	`380`	`assert(t->snapshot_no < gt->n_snapshots);`
`382`	`381`
`383`		`- return snapshot_serialize(&t->snapshot[t->snapshot_no++]);`
	`382`	`+ return snapshot_serialize(&t->snapshot[t->snapshot_no++ % MAX_SNAPSHOTS_PER_TRANS]);`
`384`	`383`	`}`
`385`	`384`
`386`	`385`	`static bool queue_for_transaction_finish(void stream, void clientdata, int node, xid_t xid, char cmd) {`
Original file line number	Diff line number	Diff line change
`@@ -68,12 +68,13 @@ static void DtmEnsureConnection(void)`
`68`	`68`	`XTM_TRACE("XTM: DtmEnsureConnection\n");`
`69`	`69`	`while (attempt < XTM_CONNECT_ATTEMPTS) {`
`70`	`70`	`if (DtmConn) {`
`71`		`- break;`
	`71`	`+ return;`
`72`	`72`	`}`
`73`	`73`	`XTM_TRACE("XTM: DtmEnsureConnection, attempt #%u\n", attempt);`
`74`	`74`	`DtmConn = DtmConnect("127.0.0.1", 5431);`
`75`	`75`	`attempt++;`
`76`	`76`	`}`
	`77`	`+ elog(ERROR, "Failed to connect to DTMD");`
`77`	`78`	`}`
`78`	`79`
`79`	`80`	`static void DumpSnapshot(Snapshot s, char *name)`