Some improvements to debug/error logging.

We now log name of the remote node and remote PID if an error is received on a
connection. Some more debugging messages added to the pooler code.

diff --git a/src/backend/pgxc/pool/pgxcnode.c b/src/backend/pgxc/pool/pgxcnode.c
index bb8e94c829031ea72e57086eb4dbc7e996e39f85..7ca3691dcd09fe620d1a9867069a065831b4c339 100644 (file)
--- a/src/backend/pgxc/pool/pgxcnode.c
+++ b/src/backend/pgxc/pool/pgxcnode.c
@@ -213,12 +213,16 @@ InitMultinodeExecutor(bool is_force)
                init_pgxc_handle(&dn_handles[count]);
                dn_handles[count].nodeoid = dnOids[count];
                dn_handles[count].nodeid = get_pgxc_node_id(dnOids[count]);
+               strncpy(dn_handles[count].nodename, get_pgxc_nodename(dnOids[count]),
+                               NAMEDATALEN);
        }
        for (count = 0; count < NumCoords; count++)
        {
                init_pgxc_handle(&co_handles[count]);
                co_handles[count].nodeoid = coOids[count];
                co_handles[count].nodeid = get_pgxc_node_id(coOids[count]);
+               strncpy(co_handles[count].nodename, get_pgxc_nodename(coOids[count]),
+                               NAMEDATALEN);
        }
 
        datanode_count = 0;
@@ -1885,7 +1889,8 @@ pgxc_node_send_timestamp(PGXCNodeHandle *handle, TimestampTz timestamp)
 void
 add_error_message(PGXCNodeHandle *handle, const char *message)
 {
-       elog(LOG, "Connection error %s", message);
+       elog(LOG, "Remote node \"%s\", running with pid %d returned an error: %s",
+                       handle->nodename, handle->backend_pid, message);
        handle->transaction_status = 'E';
        if (handle->error)
        {
@@ -1962,6 +1967,7 @@ get_any_handle(List *datanodelist)
                                        int        *pids;
                                        int    *fds = PoolManagerGetConnections(allocate, NIL,
                                                        &pids);
+                                       PGXCNodeHandle          *node_handle;
 
                                        if (!fds)
                                        {
@@ -1978,9 +1984,14 @@ get_any_handle(List *datanodelist)
                                                                         "max_connections and max_pool_size configuration "
                                                                         "parameters")));
                                        }
-                                       pgxc_node_init(&dn_handles[node], fds[0], true, pids[0]);
+                                       node_handle = &dn_handles[node];
+                                       pgxc_node_init(node_handle, fds[0], true, pids[0]);
                                        datanode_count++;
 
+                                       elog(DEBUG1, "Established a connection with datanode \"%s\","
+                                                       "remote backend PID %d, socket fd %d, global session %c",
+                                                       node_handle->nodename, (int) pids[0], fds[0], 'T');
+
                                        /*
                                         * set load_balancer for next time and return the handle
                                         */
@@ -2227,6 +2238,11 @@ get_handles(List *datanodelist, List *coordlist, bool is_coord_only_query, bool
                                pgxc_node_init(node_handle, fdsock, is_global_session, be_pid);
                                dn_handles[node] = *node_handle;
                                datanode_count++;
+
+                               elog(DEBUG1, "Established a connection with datanode \"%s\","
+                                               "remote backend PID %d, socket fd %d, global session %c",
+                                               node_handle->nodename, (int) be_pid, fdsock,
+                                               is_global_session ? 'T' : 'F');
                        }
                }
                /* Initialisation for Coordinators */
@@ -2249,6 +2265,11 @@ get_handles(List *datanodelist, List *coordlist, bool is_coord_only_query, bool
                                pgxc_node_init(node_handle, fdsock, is_global_session, be_pid);
                                co_handles[node] = *node_handle;
                                coord_count++;
+
+                               elog(DEBUG1, "Established a connection with coordinator \"%s\","
+                                               "remote backend PID %d, socket fd %d, global session %c",
+                                               node_handle->nodename, (int) be_pid, fdsock,
+                                               is_global_session ? 'T' : 'F');
                        }
                }
 

diff --git a/src/backend/pgxc/pool/poolmgr.c b/src/backend/pgxc/pool/poolmgr.c
index 95514e31a6971585a484d61f37095d3f2c05f2eb..27a3f6f99b34197b59aa2fe29602b150e002b776 100644 (file)
--- a/src/backend/pgxc/pool/poolmgr.c
+++ b/src/backend/pgxc/pool/poolmgr.c
@@ -561,6 +561,9 @@ PoolManagerConnect(const char *database, const char *user_name,
                                (errcode(ERRCODE_INTERNAL_ERROR),
                                 errmsg("failed to connect to the pooler process")));
 
+       elog(DEBUG1, "Connecting to PoolManager (user_name %s, database %s, "
+                       "pgoptions %s", user_name, database, pgoptions);
+
        /*
         * Special handling for db_user_namespace=on
         * We need to handle per-db users and global users. The per-db users will
@@ -632,6 +635,8 @@ PoolManagerConnect(const char *database, const char *user_name,
 void
 PoolManagerReconnect(void)
 {
+       elog(DEBUG1, "Reconnecting to PoolManager");
+
        /* Connected, disconnect */
        if (poolHandle)
                PoolManagerDisconnect();
@@ -655,6 +660,8 @@ PoolManagerLock(bool is_lock)
                PoolManagerConnect(get_database_name(MyDatabaseId),
                                                   GetClusterUserName(), "");
 
+       elog(DEBUG1, "Locking PoolManager");
+
        /* Message type */
        pool_putbytes(&poolHandle->port, &msgtype, 1);
 
@@ -1420,7 +1427,14 @@ agent_acquire_connections(PoolAgent *agent, List *datanodelist,
        /* Check if pooler can accept those requests */
        if (list_length(datanodelist) > agent->num_dn_connections ||
                        list_length(coordlist) > agent->num_coord_connections)
+       {
+               elog(LOG, "agent_acquire_connections called with invalid arguments -"
+                               "list_length(datanodelist) %d, num_dn_connections %d,"
+                               "list_length(coordlist) %d, num_coord_connections %d",
+                               list_length(datanodelist), agent->num_dn_connections,
+                               list_length(coordlist), agent->num_coord_connections);
                return NULL;
+       }
 
        /*
         * Allocate memory
@@ -1471,6 +1485,8 @@ agent_acquire_connections(PoolAgent *agent, List *datanodelist,
                        {
                                pfree(result);
                                MemoryContextSwitchTo(oldcontext);
+                               elog(LOG, "Pooler could not open a connection to node %d",
+                                               agent->dn_conn_oids[node]);
                                return NULL;
                        }
 
@@ -1503,6 +1519,8 @@ agent_acquire_connections(PoolAgent *agent, List *datanodelist,
                        {
                                pfree(result);
                                MemoryContextSwitchTo(oldcontext);
+                               elog(LOG, "Pooler could not open a connection to node %d",
+                                               agent->coord_conn_oids[node]);
                                return NULL;
                        }
 
@@ -1555,9 +1573,15 @@ cancel_query_on_connections(PoolAgent *agent, List *datanodelist, List *coordlis
                if (!agent->dn_connections[node])
                        continue;
 
+               elog(DEBUG1, "Canceling query on connection to remote node %d, remote pid %d",
+                               agent->dn_conn_oids[node],
+                               ((PGconn *) agent->dn_connections[node]->conn)->be_pid);
                bRet = PQcancel((PGcancel *) agent->dn_connections[node]->xc_cancelConn, errbuf, sizeof(errbuf));
                if (bRet != false)
                {
+                       elog(DEBUG1, "Cancelled query on connection to remote node %d, remote pid %d",
+                                       agent->dn_conn_oids[node],
+                                       ((PGconn *) agent->dn_connections[node]->conn)->be_pid);
                        nCount++;
                }
        }
@@ -1576,9 +1600,15 @@ cancel_query_on_connections(PoolAgent *agent, List *datanodelist, List *coordlis
                if (!agent->coord_connections[node])
                        continue;
 
+               elog(DEBUG1, "Canceling query on connection to remote node %d, remote pid %d",
+                               agent->coord_conn_oids[node],
+                               ((PGconn *) agent->coord_connections[node]->conn)->be_pid);
                bRet = PQcancel((PGcancel *) agent->coord_connections[node]->xc_cancelConn, errbuf, sizeof(errbuf));
                if (bRet != false)
                {
+                       elog(DEBUG1, "Cancelled query on connection to remote node %d, remote pid %d",
+                                       agent->coord_conn_oids[node],
+                                       ((PGconn *) agent->coord_connections[node]->conn)->be_pid);
                        nCount++;
                }
        }
@@ -1600,6 +1630,8 @@ PoolManagerReleaseConnections(bool force)
        if (!poolHandle)
                return;
 
+       elog(DEBUG1, "Returning connections back to the pool");
+
        /* Message type */
        pool_putbytes(&poolHandle->port, &msgtype, 1);
 
@@ -1710,6 +1742,7 @@ agent_release_connections(PoolAgent *agent, bool force_destroy)
                if (slot)
                        release_connection(agent->pool, slot, agent->dn_conn_oids[i], force_destroy);
                agent->dn_connections[i] = NULL;
+               elog(DEBUG1, "Released connection to node %d", agent->dn_conn_oids[i]);
        }
        /* Then clean up for Coordinator connections */
        for (i = 0; i < agent->num_coord_connections; i++)
@@ -1723,6 +1756,7 @@ agent_release_connections(PoolAgent *agent, bool force_destroy)
                if (slot)
                        release_connection(agent->pool, slot, agent->coord_conn_oids[i], force_destroy);
                agent->coord_connections[i] = NULL;
+               elog(DEBUG1, "Released connection to node %d", agent->coord_conn_oids[i]);
        }
 
        /*
@@ -1753,6 +1787,9 @@ create_database_pool(const char *database, const char *user_name, const char *pg
        HASHCTL                 hinfo;
        int                             hflags;
 
+       elog(DEBUG1, "Creating a connection pool for database %s, user %s,"
+                       " with pgoptions %s", database, user_name, pgoptions);
+
        dbcontext = AllocSetContextCreate(PoolerCoreContext,
                                                                          "DB Context",
                                                                          ALLOCSET_DEFAULT_MINSIZE,
@@ -1824,6 +1861,9 @@ destroy_database_pool(const char *database, const char *user_name)
 {
        DatabasePool *databasePool;
 
+       elog(DEBUG1, "Destroy a connection pool to database %s, user %s",
+                       database, user_name);
+
        /* Delete from the list */
        databasePool = remove_database_pool(database, user_name);
        if (databasePool)
@@ -1870,6 +1910,8 @@ reload_database_pools(PoolAgent *agent)
 {
        DatabasePool *databasePool;
 
+       elog(DEBUG1, "Reloading database pools");
+
        /*
         * Release node connections if any held. It is not guaranteed client session
         * does the same so don't ever try to return them to pool and reuse

diff --git a/src/include/pgxc/pgxcnode.h b/src/include/pgxc/pgxcnode.h
index d57aabe18be403466e7897540b885b633f2dab6b..e19bbfe2b8cea416d747dc36ea2ad617afd46e1e 100644 (file)
--- a/src/include/pgxc/pgxcnode.h
+++ b/src/include/pgxc/pgxcnode.h
@@ -63,6 +63,7 @@ struct pgxc_node_handle
 {
        Oid                     nodeoid;
        int                     nodeid;
+       char            nodename[NAMEDATALEN];
 
        /* fd of the connection */
        int             sock;