在写这篇文章之前，xxx已经写过了几篇关于改事务内容主题的文章,想要了解的朋友可以去翻一下之前的文章
pgbench is a benchmarking tool for PostgreSQL ,pgbench是postgresql自带的一个性能基准测试工具。
可以通过pgbench --help看一下参数的相关信息
Usage:
pgbench [OPTIONS]... [DBNAME]
Initialization options:
-i invokes initialization mode
-F NUM fill factor
-s NUM scaling factor
Benchmarking options:
-c NUM number of concurrent database clients (default: 1)
-C establish new connection for each transaction
-D VARNAME=VALUE
define variable for use by custom script
-f FILENAME read transaction script from FILENAME
-j NUM number of threads (default: 1)
-l write transaction times to log file
-M {simple|extended|prepared}
protocol for submitting queries to server (default: simple)
-n do not run VACUUM before tests
-N do not update tables "pgbench_tellers" and "pgbench_branches"
-r report average latency per command
-s NUM report this scale factor in output
-S perform SELECT-only transactions
-t NUM number of transactions each client runs (default: 10)
-T NUM duration of benchmark test in seconds
-v vacuum all four standard tables before tests
Common options:
-d print debugging output
-h HOSTNAME database server host or socket directory
-p PORT database server port number
-U USERNAME connect as specified database user
--help show this help, then exit
--version output version information, then exit
初始化：scale为10，pgbench_accounts记录有100W，
pgbench -i -s 10 pgbench -h 127.0.0.1 -p 1931 -U testuser
这里初始化会创立4张表，如下
Schema | Name | Type | Owner | Size | Description
--------+------------------+-------+----------+--------+-------------
public | pgbench_accounts | table | testuser | 130 MB |
public | pgbench_branches | table | testuser | 168 kB |
public | pgbench_history | table | testuser | 960 kB |
public | pgbench_tellers | table | testuser | 456 kB |
测试：100个client并发，每一个有100个事务
pgbench -c 100 -t 100 pgbench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 10
query mode: simple
number of clients: 100
number of threads: 1
number of transactions per client: 100
number of transactions actually processed: 10000/10000
tps = 114.339158 (including connections establishing) --包括网络开销的事务数
tps = 114.643324 (excluding connections establishing) --不包括网络开销的事务数
pgbench -c 100 -t 100 -j 100 pgbench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 10
query mode: simple
number of clients: 100
number of threads: 100
number of transactions per client: 100
number of transactions actually processed: 10000/10000
tps = 134.473603 (including connections establishing)
tps = 134.616838 (excluding connections establishing)
这里注意-c必须是-j的倍数，也就是client是threads的倍数。
pgbench -c 100 -j 100 -T 10 pgbench
starting vacuum...end.
transaction type: TPC-B (sort of)
scaling factor: 10
query mode: simple
number of clients: 100
number of threads: 100
duration: 10 s
number of transactions actually processed: 2144
tps = 209.617862 (including connections establishing)
tps = 211.282453 (excluding connections establishing)
注意：-t和-T不能同时使用，
脚本的内容：
\set nbranches :scale
\set ntellers 10 * :scale
\set naccounts 100000 * :scale
\setrandom aid 1 :naccounts
\setrandom bid 1 :nbranches
\setrandom tid 1 :ntellers
\setrandom delta -5000 5000
BEGIN;
UPDATE pgbench_accounts SET abalance = abalance + :delta WHERE aid = :aid;
SELECT abalance FROM pgbench_accounts WHERE aid = :aid;
UPDATE pgbench_tellers SET tbalance = tbalance + :delta WHERE tid = :tid;
UPDATE pgbench_branches SET bbalance = bbalance + :delta WHERE bid = :bid;
INSERT INTO pgbench_history (tid, bid, aid, delta, mtime) VALUES (:tid, :bid, :aid, :delta, CURRENT_TIMESTAMP);
END;
举例测试一下呆板insert的速度有多快
insertsize.sql内容：create table data(filler text);
insert-size.sql内容：insert into data (filler) values (repeat('X',:scale));
$psql -d pgbench -f insertsize.sql
$pgbench -s 100 -c 10 -t 10000 pgbench -f insert-size.sql
starting vacuum...end.
transaction type: Custom query
scaling factor: 100
query mode: simple
number of clients: 10
number of threads: 1
number of transactions per client: 10000
number of transactions actually processed: 100000/100000
tps = 608.144907 (including connections establishing)
tps = 608.234303 (excluding connections establishing)
文章结束给大家分享下程序员的一些笑话语录：
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