Hi,
I've written a small patch to add support for pow() in pgbench.
The main reason behind it is that I'm currently using a shell call to do it
which takes between 2-10 ms that can be a big percentage of the time taken
by the whole transaction. For example (shortened):
latency average = 11.718 ms
- statement latencies in milliseconds:
2.834 \setshell POWER2 awk 'BEGIN {p=2^ARGV[1]; print p }'
:ZOOM_CURRENT
8.846 SELECT
ST_AsBinary(ST_Simplify(ST_SnapToGrid("the_geom_webmercator",:SNAP),
:SIMPLIFY)) AS geom FROM
I've also updated the related docs and added some tests. Please let me know
if I'm missing anything.
Regards,
*Raúl Marín Rodríguez*
carto.com
From 08a4d519e0c73d0f16acd9e5db9e5b547a884902 Mon Sep 17 00:00:00 2001
From: Raul Marin <rmrodrig...@cartodb.com>
Date: Fri, 13 Oct 2017 17:42:23 +0200
Subject: [PATCH] Add pow() support to pgbench
---
doc/src/sgml/ref/pgbench.sgml | 7 +++++++
src/bin/pgbench/exprparse.y | 3 +++
src/bin/pgbench/pgbench.c | 9 +++++++++
src/bin/pgbench/pgbench.h | 3 ++-
src/bin/pgbench/t/001_pgbench_with_server.pl | 7 ++++++-
5 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/doc/src/sgml/ref/pgbench.sgml b/doc/src/sgml/ref/pgbench.sgml
index e509e6c7f62..e12a149c5bb 100644
--- a/doc/src/sgml/ref/pgbench.sgml
+++ b/doc/src/sgml/ref/pgbench.sgml
@@ -1022,6 +1022,13 @@ pgbench <optional> <replaceable>options</replaceable> </optional> <replaceable>d
<entry><literal>sqrt(2.0)</literal></entry>
<entry><literal>1.414213562</literal></entry>
</row>
+ <row>
+ <entry><literal><function>pow(<replaceable>x</replaceable>, <replaceable>y</replaceable>)</function></literal></entry>
+ <entry>double if <replaceable>x</replaceable> or <replaceable>y</replaceable> are doubles, else integer</entry>
+ <entry>Numeric exponentiation</entry>
+ <entry><literal>pow(2.0, 10)</literal></entry>
+ <entry><literal>1024.0/<literal></entry>
+ </row>
</tbody>
</tgroup>
</table>
diff --git a/src/bin/pgbench/exprparse.y b/src/bin/pgbench/exprparse.y
index b3a2d9bfd37..4db3b215abf 100644
--- a/src/bin/pgbench/exprparse.y
+++ b/src/bin/pgbench/exprparse.y
@@ -191,6 +191,9 @@ static const struct
{
"random_exponential", 3, PGBENCH_RANDOM_EXPONENTIAL
},
+ {
+ "pow", 2, PGBENCH_POW
+ },
/* keep as last array element */
{
NULL, 0, 0
diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index 5d8a01c72cf..a3aef108f84 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -1346,6 +1346,7 @@ evalFunc(TState *thread, CState *st,
case PGBENCH_MUL:
case PGBENCH_DIV:
case PGBENCH_MOD:
+ case PGBENCH_POW:
{
PgBenchValue *lval = &vargs[0],
*rval = &vargs[1];
@@ -1381,6 +1382,10 @@ evalFunc(TState *thread, CState *st,
setDoubleValue(retval, ld / rd);
return true;
+ case PGBENCH_POW:
+ setDoubleValue(retval, pow(ld, rd));
+ return true;
+
default:
/* cannot get here */
Assert(0);
@@ -1442,6 +1447,10 @@ evalFunc(TState *thread, CState *st,
return true;
+ case PGBENCH_POW:
+ setIntValue(retval, pow(li, ri));
+ return true;
+
default:
/* cannot get here */
Assert(0);
diff --git a/src/bin/pgbench/pgbench.h b/src/bin/pgbench/pgbench.h
index fd428af274f..e0132b5fcf6 100644
--- a/src/bin/pgbench/pgbench.h
+++ b/src/bin/pgbench/pgbench.h
@@ -75,7 +75,8 @@ typedef enum PgBenchFunction
PGBENCH_SQRT,
PGBENCH_RANDOM,
PGBENCH_RANDOM_GAUSSIAN,
- PGBENCH_RANDOM_EXPONENTIAL
+ PGBENCH_RANDOM_EXPONENTIAL,
+ PGBENCH_POW
} PgBenchFunction;
typedef struct PgBenchExpr PgBenchExpr;
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index 11bc0fecfef..601c7ee0e4d 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -218,7 +218,9 @@ sub pgbench
qr{command=18.: double 18\b},
qr{command=19.: double 19\b},
qr{command=20.: double 20\b},
- qr{command=21.: int 9223372036854775807\b}, ],
+ qr{command=21.: int 9223372036854775807\b},
+ qr{command=23.: int -27\b},
+ qr{command=24.: double 1024\b}, ],
'pgbench expressions',
{ '001_pgbench_expressions' => q{-- integer functions
\set i1 debug(random(1, 100))
@@ -248,6 +250,9 @@ sub pgbench
\set maxint debug(:minint - 1)
-- reset a variable
\set i1 0
+--- pow() operator
+\set poweri debug(pow(-3,3))
+\set powerd debug(pow(2.0,10))
} });
# backslash commands
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