From 27e1f14563cf982f1f4d71e21ef247866662a052 Mon Sep 17 00:00:00 2001 From: Etsuro Fujita Date: Wed, 31 Mar 2021 18:45:00 +0900 Subject: Add support for asynchronous execution. This implements asynchronous execution, which runs multiple parts of a non-parallel-aware Append concurrently rather than serially to improve performance when possible. Currently, the only node type that can be run concurrently is a ForeignScan that is an immediate child of such an Append. In the case where such ForeignScans access data on different remote servers, this would run those ForeignScans concurrently, and overlap the remote operations to be performed simultaneously, so it'll improve the performance especially when the operations involve time-consuming ones such as remote join and remote aggregation. We may extend this to other node types such as joins or aggregates over ForeignScans in the future. This also adds the support for postgres_fdw, which is enabled by the table-level/server-level option "async_capable". The default is false. Robert Haas, Kyotaro Horiguchi, Thomas Munro, and myself. This commit is mostly based on the patch proposed by Robert Haas, but also uses stuff from the patch proposed by Kyotaro Horiguchi and from the patch proposed by Thomas Munro. Reviewed by Kyotaro Horiguchi, Konstantin Knizhnik, Andrey Lepikhov, Movead Li, Thomas Munro, Justin Pryzby, and others. Discussion: https://postgr.es/m/CA%2BTgmoaXQEt4tZ03FtQhnzeDEMzBck%2BLrni0UWHVVgOTnA6C1w%40mail.gmail.com Discussion: https://postgr.es/m/CA%2BhUKGLBRyu0rHrDCMC4%3DRn3252gogyp1SjOgG8SEKKZv%3DFwfQ%40mail.gmail.com Discussion: https://postgr.es/m/20200228.170650.667613673625155850.horikyota.ntt%40gmail.com --- contrib/postgres_fdw/postgres_fdw.h | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) (limited to 'contrib/postgres_fdw/postgres_fdw.h') diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index 1f67b4d9fd2..88d94da6f6b 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -16,6 +16,7 @@ #include "foreign/foreign.h" #include "lib/stringinfo.h" #include "libpq-fe.h" +#include "nodes/execnodes.h" #include "nodes/pathnodes.h" #include "utils/relcache.h" @@ -78,6 +79,7 @@ typedef struct PgFdwRelationInfo Cost fdw_startup_cost; Cost fdw_tuple_cost; List *shippable_extensions; /* OIDs of shippable extensions */ + bool async_capable; /* Cached catalog information. */ ForeignTable *table; @@ -124,17 +126,28 @@ typedef struct PgFdwRelationInfo int relation_index; } PgFdwRelationInfo; +/* + * Extra control information relating to a connection. + */ +typedef struct PgFdwConnState +{ + AsyncRequest *pendingAreq; /* pending async request */ +} PgFdwConnState; + /* in postgres_fdw.c */ extern int set_transmission_modes(void); extern void reset_transmission_modes(int nestlevel); +extern void process_pending_request(AsyncRequest *areq); /* in connection.c */ -extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt); +extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt, + PgFdwConnState **state); extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); extern PGresult *pgfdw_get_result(PGconn *conn, const char *query); -extern PGresult *pgfdw_exec_query(PGconn *conn, const char *query); +extern PGresult *pgfdw_exec_query(PGconn *conn, const char *query, + PgFdwConnState *state); extern void pgfdw_report_error(int elevel, PGresult *res, PGconn *conn, bool clear, const char *sql); -- cgit v1.2.3