diff options
| author | Tatsuo Ishii | 2021-09-02 01:39:09 +0000 |
|---|---|---|
| committer | Tatsuo Ishii | 2021-09-02 01:39:09 +0000 |
| commit | 06ba4a63b85e5aa47b325c3235c16c05a0b58b96 (patch) | |
| tree | 6314f1e5ebbf3424b10fab49e5923972dfe1b40a | |
| parent | 469150a240dd79acbe7d86cb5df869d95f4d6d2d (diff) | |
Use COPY FREEZE in pgbench for faster benchmark table population.
While populating the pgbench_accounts table, plain COPY was
unconditionally used. By changing it to COPY FREEZE, the time for
VACUUM is significantly reduced, thus the total time of "pgbench -i"
is also reduced. This only happens if pgbench runs against PostgreSQL
14 or later because COPY FREEZE in previous versions of PostgreSQL does
not bring the benefit. Also if partitioning is used, COPY FREEZE
cannot be used. In this case plain COPY will be used too.
Author: Tatsuo Ishii
Discussion: https://postgr.es/m/20210308.143907.2014279678657453983.t-ishii@gmail.com
Reviewed-by: Fabien COELHO, Laurenz Albe, Peter Geoghegan, Dean Rasheed
| -rw-r--r-- | doc/src/sgml/ref/pgbench.sgml | 3 | ||||
| -rw-r--r-- | src/bin/pgbench/pgbench.c | 11 |
2 files changed, 13 insertions, 1 deletions
diff --git a/doc/src/sgml/ref/pgbench.sgml b/doc/src/sgml/ref/pgbench.sgml index 0c60077e1f9..0f432767c25 100644 --- a/doc/src/sgml/ref/pgbench.sgml +++ b/doc/src/sgml/ref/pgbench.sgml @@ -220,6 +220,9 @@ pgbench <optional> <replaceable>options</replaceable> </optional> <replaceable>d data is generated in <command>pgbench</command> client and then sent to the server. This uses the client/server bandwidth extensively through a <command>COPY</command>. + <command>pgbench</command> uses the FREEZE option with 14 or later + versions of <productname>PostgreSQL</productname> to speed up + subsequent <command>VACUUM</command>, unless partitions are enabled. Using <literal>g</literal> causes logging to print one message every 100,000 rows while generating data for the <structname>pgbench_accounts</structname> table. diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c index a33c91dceda..4c9952a85a6 100644 --- a/src/bin/pgbench/pgbench.c +++ b/src/bin/pgbench/pgbench.c @@ -4153,6 +4153,7 @@ initGenerateDataClientSide(PGconn *con) PGresult *res; int i; int64 k; + char *copy_statement; /* used to track elapsed time and estimate of the remaining time */ pg_time_usec_t start; @@ -4199,7 +4200,15 @@ initGenerateDataClientSide(PGconn *con) /* * accounts is big enough to be worth using COPY and tracking runtime */ - res = PQexec(con, "copy pgbench_accounts from stdin"); + + /* use COPY with FREEZE on v14 and later without partioning */ + if (partitions == 0 && PQserverVersion(con) >= 140000) + copy_statement = "copy pgbench_accounts from stdin with (freeze on)"; + else + copy_statement = "copy pgbench_accounts from stdin"; + + res = PQexec(con, copy_statement); + if (PQresultStatus(res) != PGRES_COPY_IN) { pg_log_fatal("unexpected copy in result: %s", PQerrorMessage(con)); |