add a check to skip checksum for diskless replication

Signed-off-by: Shivshankar-Reddy <[email protected]>

src/rdb.c

@@ -1407,7 +1407,7 @@ int rdbSaveRio(int req, rio *rdb, int *error, int rdbflags, rdbSaveInfo *rsi) {
     long key_counter = 0;
     int j;
 
-    if (server.rdb_checksum) rdb->update_cksum = rioGenericUpdateChecksum;
+    if (server.rdb_checksum && !(rdbflags & RDBFLAGS_CKSUM_SKIP)) rdb->update_cksum = rioGenericUpdateChecksum;
     snprintf(magic, sizeof(magic), "REDIS%04d", RDB_VERSION);
     if (rdbWriteRaw(rdb, magic, 9) == -1) goto werr;
     if (rdbSaveInfoAuxFields(rdb, rdbflags, rsi) == -1) goto werr;
@@ -1451,14 +1451,17 @@ int rdbSaveRio(int req, rio *rdb, int *error, int rdbflags, rdbSaveInfo *rsi) {
  * without doing any processing of the content. */
 int rdbSaveRioWithEOFMark(int req, rio *rdb, int *error, rdbSaveInfo *rsi) {
     char eofmark[RDB_EOF_MARK_SIZE];
+    int skip_cksum_repl = RDBFLAGS_REPLICATION;
 
     startSaving(RDBFLAGS_REPLICATION);
     getRandomHexChars(eofmark, RDB_EOF_MARK_SIZE);
     if (error) *error = 0;
     if (rioWrite(rdb, "$EOF:", 5) == 0) goto werr;
     if (rioWrite(rdb, eofmark, RDB_EOF_MARK_SIZE) == 0) goto werr;
     if (rioWrite(rdb, "\r\n", 2) == 0) goto werr;
-    if (rdbSaveRio(req, rdb, error, RDBFLAGS_REPLICATION, rsi) == C_ERR) goto werr;
+    if (server.repl_diskless_sync && req & REPLICA_REQ_CHKSUM_SKIP)
+        skip_cksum_repl |= RDBFLAGS_CKSUM_SKIP;
+    if (rdbSaveRio(req, rdb, error, skip_cksum_repl, rsi) == C_ERR) goto werr;
     if (rioWrite(rdb, eofmark, RDB_EOF_MARK_SIZE) == 0) goto werr;
     stopSaving(1);
     return C_OK;

src/rdb.h

@@ -133,6 +133,7 @@
 #define RDBFLAGS_ALLOW_DUP (1 << 2)    /* Allow duplicated keys when loading.*/
 #define RDBFLAGS_FEED_REPL (1 << 3)    /* Feed replication stream when loading.*/
 #define RDBFLAGS_KEEP_CACHE (1 << 4)   /* Don't reclaim cache after rdb file is generated */
+#define RDBFLAGS_CKSUM_SKIP (1 << 5)   /* Skip checksum for diskless sync. */
 
 /* When rdbLoadObject() returns NULL, the err flag is
  * set to hold the type of error that occurred */

src/replication.c

@@ -1109,9 +1109,11 @@ void syncCommand(client *c) {
         }
 
         if (primaryTryPartialResynchronization(c, psync_offset) == C_OK) {
+            serverLog(LL_NOTICE, "===> completed partial resync");
             server.stat_sync_partial_ok++;
             return; /* No full resync needed, return. */
         } else {
+            serverLog(LL_NOTICE, "===> completed partial resync with failure");
             char *primary_replid = c->argv[1]->ptr;
 
             /* Increment stats for failed PSYNCs, but only if the
@@ -1271,6 +1273,9 @@ void syncCommand(client *c) {
  * - rdb-channel <1|0>
  * Used to identify the client as a replica's rdb connection in an dual channel
  * sync session.
+ *
+ * - repl-diskless-load <1|0>
+ * Replica is capable of load data from replication stream, request to skip checksum.
  * */
 void replconfCommand(client *c) {
     int j;
@@ -1313,6 +1318,13 @@ void replconfCommand(client *c) {
                  * replconf option. */
                 c->replica_capa |= REPLICA_CAPA_DUAL_CHANNEL;
             }
+         } else if (!strcasecmp(c->argv[j]->ptr, "repl-diskless-load")) {
+            /* REPLCONF repl-diskless-load is used to identify the client is capable of
+             * load directly without creating rdb file */
+            long rdb_diskless_load = 0;
+            if (getRangeLongFromObjectOrReply(c, c->argv[j + 1], 0, 1, &rdb_diskless_load, NULL) != C_OK) return;
+            if (rdb_diskless_load == 1)
+                c->replica_req |= REPLICA_REQ_CHKSUM_SKIP;
         } else if (!strcasecmp(c->argv[j]->ptr, "ack")) {
             /* REPLCONF ACK is used by replica to inform the primary the amount
              * of replication stream that it processed so far. It is an
@@ -2632,7 +2644,7 @@ static void fullSyncWithPrimary(connection *conn) {
         /* Send replica lisening port to primary for clarification */
         sds portstr = getReplicaPortString();
         err = sendCommand(conn, "REPLCONF", "capa", "eof", "rdb-only", "1", "rdb-channel", "1", "listening-port",
-                          portstr, NULL);
+                          portstr, "repl-diskless-load", useDisklessLoad() ? "1" : "0", NULL);
         sdsfree(portstr);
         if (err) {
             serverLog(LL_WARNING, "Sending command to primary in dual channel replication handshake: %s", err);
@@ -3427,6 +3439,11 @@ void syncWithPrimary(connection *conn) {
             if (err) goto write_error;
         }
 
+        if (useDisklessLoad()) {
+            err = sendCommand(conn, "REPLCONF", "repl-diskless-load", "1", NULL);
+            if (err) goto write_error;
+        }
+
         /* Inform the primary of our (replica) capabilities.
          *
          * EOF: supports EOF-style RDB transfer for diskless replication.

src/server.h

@@ -438,6 +438,8 @@ typedef enum {
 #define REPLICA_REQ_RDB_EXCLUDE_DATA (1 << 0)      /* Exclude data from RDB */
 #define REPLICA_REQ_RDB_EXCLUDE_FUNCTIONS (1 << 1) /* Exclude functions from RDB */
 #define REPLICA_REQ_RDB_CHANNEL (1 << 2)           /* Use dual-channel-replication */
+#define REPLICA_REQ_CHKSUM_SKIP (1 << 3)           /* Exclude checksum from RDB */
+
 /* Mask of all bits in the replica requirements bitfield that represent non-standard (filtered) RDB requirements */
 #define REPLICA_REQ_RDB_MASK (REPLICA_REQ_RDB_EXCLUDE_DATA | REPLICA_REQ_RDB_EXCLUDE_FUNCTIONS)