added psycopg2 and libpq results

* COMMENT -*- mode: org -*-

#+Date: 2016-12-16

Time-stamp: <2016-12-16>

* database binding benchmark

I want to know the efficiency of the db binding for different language,

libraries and database servers.

- table:

  CREATE TABLE foo

  (id integer primary key,

   bar integer);

  INSERT INTO foo (id, bar) VALUES (1, 1);

- run many times:

  SELECT * FROM foo

  UPDATE foo SET bar=bar+1 WHERE id=1

* benchmark results

** postgres 9.4, cpython 2.7, psycopg2==2.6.1

http://initd.org/psycopg/docs/usage.html

0.35

28.77

--

0.38

26.15

--

0.37

26.35

** postgres 9.4, C, libpq5

https://www.postgresql.org/docs/9.4/static/libpq.html

0.33

26.6

--

0.32

26.5

--

0.30

26.2

//side note: why adding -shared in LDFLAGS will just segfault the program?

CFLAGS = -std=c99 -O2 -fPIC -pedantic -Wall -Wextra -I/usr/include/postgresql

LDFLAGS = -lpq

bench: bench.c

/**

 * run simple select and update benchmark.

 */

#include <stdio.h>

#include <stdlib.h>

#include <sys/time.h>

#include <libpq-fe.h>

#define TIMES 3000

static void

exit_nicely(PGconn *conn)

{

    PQfinish(conn);

    exit(1);

}

void

select_test(PGconn *conn)

{

	PGresult *res;

	for (int i = 0; i < TIMES; ++i) {

		res = PQexec(conn, "SELECT id, bar FROM foo");

		if (PQresultStatus(res) != PGRES_TUPLES_OK)

		{

			fprintf(stderr, "SELECT command failed: %s",

				PQerrorMessage(conn));

			PQclear(res);

			exit_nicely(conn);

		}

		PQclear(res);

	}

}

void

update_test(PGconn *conn)

{

	PGresult *res;

	for (int i = 0; i < TIMES; ++i) {

		res = PQexec(conn, "UPDATE foo SET bar=bar+1 WHERE id=1");

		if (PQresultStatus(res) != PGRES_COMMAND_OK)

		{

			fprintf(stderr, "UPDATE command failed: %s",

				PQerrorMessage(conn));

			PQclear(res);

			exit_nicely(conn);

		}

		PQclear(res);

	}

}

double diff_microseconds(struct timeval *start, struct timeval *end)

{

	return (double)((end->tv_sec * 1000000 + end->tv_usec) -

			(start->tv_sec * 1000000 + start->tv_usec));

}

int

main()

{

	struct timeval start, end;

	const char *conninfo = "host=localhost dbname=t1 user=t1 password=fNfwREMqO69TB9YqE+/OzF5/k+s=";

	PGconn *conn;

	conn = PQconnectdb(conninfo);

	if (PQstatus(conn) != CONNECTION_OK)

	{

		fprintf(stderr, "Connection to database failed: %s",

			PQerrorMessage(conn));

		exit_nicely(conn);

	}

	gettimeofday(&start, NULL);

	select_test(conn);

	gettimeofday(&end, NULL);

	printf("%.3f\n", diff_microseconds(&start, &end) / 1000000.0);

	gettimeofday(&start, NULL);

	update_test(conn);

	gettimeofday(&end, NULL);

	printf("%.3f\n", diff_microseconds(&start, &end) / 1000000.0);

	PQfinish(conn);

	return 0;

}

#!/usr/bin/env python

# coding=utf-8

"""

run db benchmark

"""

from contextlib import contextmanager

import logging

import psycopg2

from yygame.debug import trace_time

logging.basicConfig(format='%(levelname)-8s %(message)s', level=logging.DEBUG)

logger = logging.getLogger('')

@trace_time()

def select_test(conn, times=3000):

    cur = conn.cursor()

    for i in range(times):

        cur.execute(u"""\

SELECT id, bar FROM foo

""")

        cur.fetchone()

@trace_time()

def update_test(conn, times=3000):

    cur = conn.cursor()

    for i in range(times):

        cur.execute(u"""\

UPDATE foo SET bar=bar+1 WHERE id=1

""")

        conn.commit()

def main():

    conn = psycopg2.connect(host="localhost",

                            database="t1",

                            user="t1",

                            password="fNfwREMqO69TB9YqE+/OzF5/k+s=")

    logger.info("running benchmark...")

    select_test(conn)

    update_test(conn)

if __name__ == '__main__':

    main()