摘要： 本文主要介绍并测试一下PostgreSQL 在中高端x86服务器上的数据插入速度，帮助企业用户了解PostgreSQL在这种纯插入场景的性能。（例如运营商网关数据，金融行业数据，产生量大，并且要求快速插入大数据库中持久化保存。） 测试结果写在前面：每32K的block存储89条记录, 每条记录约3

本文主要介绍并测试PostgreSQL 在中高端x86服务器上的数据插入速度（目标表包含一个时间字段的索引），帮助企业用户了解PostgreSQL在这类场景下的性能表现。这类场景常见于 : 运营商网关数据，金融行业数据，产生量大，并且要求快速插入大数据库中持久化保存。另外, 用户如果需要流式实时处理，可以参考基于PostgreSQL的流式处理方案，一天处理1万亿的实时流式处理是如何实现的？https://yq.aliyun.com/articles/166

TEST CASE

.1. 平均每条记录长度360字节， (比较常见的长度) .2. 时间字段创建索引。.3. 每轮测试插入12TB数据，插入完12T后清除数据继续插入。循环。.4. 测试满24小时停止测试。.5. 统计24小时插入的记录数。

TEST 结果

24小时一共完成12轮测试，平均每轮测试耗时7071秒。506万行/s，1.78 GB/s，全天插入4372亿，154TB数据。

测试的硬件环境

.1. X86服务器     .2. 3?核。   .3. 5??G 内存   .4. 几块SSD，15TB容量   
软件环境
.1. CENTOS 6.x x64   .2 .xfs   .3. PostgreSQL 9.5   
系统配置参考
https://github.com/digoal/pgsql_admin_script/blob/master/pgsql_perf_tuning.md
数据库配置
./configure --PRefix=/home/digoal/pgsql9.5.1 --with-blocksize=32 --with-segsize=128 --with-wal-blocksize=32 --with-wal-segsize=64  make && make install  
PostgreSQL支持hugepage的方法请参考：https://yq.aliyun.com/articles/8482参数
listen_addresses = '0.0.0.0'            # what IP address(es) to listen on;fsync=onport = 1921                             # (change requires restart)max_connections = 600                   # (change requires restart)superuser_reserved_connections = 13     # (change requires restart)unix_socket_directories = '.'   # comma-separated list of directoriesunix_socket_permissions = 0700          # begin with 0 to use octal notationtcp_keepalives_idle = 60                # TCP_KEEPIDLE, in seconds;tcp_keepalives_interval = 10            # TCP_KEEPINTVL, in seconds;tcp_keepalives_count = 10               # TCP_KEEPCNT;shared_buffers = 256GB                   # min 128kBhuge_pages = on                 # on, off, or trywork_mem = 512MB                                # min 64kBmaintenance_work_mem = 1GB              # min 1MBautovacuum_work_mem = 1GB               # min 1MB, or -1 to use maintenance_work_memdynamic_shared_memory_type = posix      # the default is the first optionbgwriter_delay = 10ms                   # 10-10000ms between roundsbgwriter_lru_maxpages = 1000            # 0-1000 max buffers written/roundbgwriter_lru_multiplier = 2.0  synchronous_commit = off                # synchronization level;full_page_writes = on                  # recover from partial page writeswal_buffers = 2047MB                    # min 32kB, -1 sets based on shared_bufferswal_writer_delay = 10ms         # 1-10000 millisecondscheckpoint_timeout = 55min              # range 30s-1hmax_wal_size = 512GBcheckpoint_completion_target = 0.9      # checkpoint target duration, 0.0 - 1.0effective_cache_size = 40GB   log_destination = 'csvlog'              # Valid values are combinations oflogging_collector = on          # Enable capturing of stderr and csvloglog_directory = 'pg_log'                # directory where log files are written,log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log' # log file name pattern,log_file_mode = 0600                    # creation mode for log files,log_truncate_on_rotation = on           # If on, an existing log file with thelog_checkpoints = offlog_connections = offlog_disconnections = offlog_error_verbosity = verbose           # terse, default, or verbose messageslog_timezone = 'PRC'log_autovacuum_min_duration = 0 # -1 disables, 0 logs all actions anddatestyle = 'iso, mdy'timezone = 'PRC'lc_messages = 'C'                       # locale for system error messagelc_monetary = 'C'                       # locale for monetary formattinglc_numeric = 'C'                        # locale for number formattinglc_time = 'C'                           # locale for time formattingdefault_text_search_config = 'pg_catalog.english'autovacuum=off
创建测试表 :每32K的block存储89条记录, 每条记录360字节。
postgres=# select string_agg(i,'') from (select md5(random()::text) i from generate_series(1,10) t(i)) t(i);                               string_agg                                                                       ---------------------------------------------------------------------- 53d3ec7adbeacc912a45bdd8557b435be848e4b1050dc0f5e46b75703d4745833541b5dabc177db460b6b1493961fc72c478daaaac74bcc89aec4f946a496028d9cff1cc4144f738e01ea36436455c216aa697d87fe1f87ceb49134a687dc69cba34c9951d0c9ce9ca82bba229d56874af40498dca5fd8dfb9c877546db76c35a3362d6bdba6472d3919289b6eaeeab58feb4f6e79592fc1dd8253fd4c588a29(1 row)postgres=# create unlogged table test(crt_time timestamp, info text default '53d3ec7adbeacc912a45bdd8557b435be848e4b1050dc0f5e46b75703d4745833541b5dabc177db460b6b1493961fc72c478daaaac74bcc89aec4f946a496028d9cff1cc4144f738e01ea36436455c216aa697d87fe1f87ceb49134a687dc69cba34c9951d0c9ce9ca82bba229d56874af40498dca5fd8dfb9c877546db76c35a3362d6bdba6472d3919289b6eaeeab58feb4f6e79592fc1dd8253fd4c588a29');postgres=# alter table test alter column info set storage plain;postgres=# insert into test select now() from generate_series(1,1000);postgres=# select ctid from test limit 1000;
分别在3个物理块设备上创建3个表空间目录，同时在数据库中创建表空间。 tbs1, tbs2, tbs3.
创建多个分表，用于减少 block extend 冲突。
do language plpgsql $$declarei int;sql text;begin  for i in 1..42 loop    sql := 'create unlogged table test'||i||' (like test including all) tablespace tbs1';    execute sql;    sql := 'create index idx_test'||i||' on test'||i||' using brin (crt_time) with (pages_per_range=512) tablespace tbs1';    execute sql;  end loop;  for i in 43..84 loop    sql := 'create unlogged table test'||i||' (like test including all) tablespace tbs2';    execute sql;    sql := 'create index idx_test'||i||' on test'||i||' using brin (crt_time) with (pages_per_range=512) tablespace tbs2';    execute sql;  end loop;  for i in 85..128 loop    sql := 'create unlogged table test'||i||' (like test including all) tablespace tbs3';    execute sql;    sql := 'create index idx_test'||i||' on test'||i||' using brin (crt_time) with (pages_per_range=512) tablespace tbs3';    execute sql;  end loop;end; $$;
又见黑科技 BRIN 索引方法
这里使用的是brin范围索引，PostgreSQL 针对物联网流式数据的黑科技。
postgres=# /di                 List of relations Schema |    Name     | Type  |  Owner   |  Table  --------+-------------+-------+----------+--------- public | idx_test1   | index | postgres | test1 public | idx_test10  | index | postgres | test10 public | idx_test100 | index | postgres | test100 public | idx_test101 | index | postgres | test101 public | idx_test102 | index | postgres | test102 public | idx_test103 | index | postgres | test103 public | idx_test104 | index | postgres | test104 public | idx_test105 | index | postgres | test105 public | idx_test106 | index | postgres | test106............ public | idx_test90  | index | postgres | test90 public | idx_test91  | index | postgres | test91 public | idx_test92  | index | postgres | test92 public | idx_test93  | index | postgres | test93 public | idx_test94  | index | postgres | test94 public | idx_test95  | index | postgres | test95 public | idx_test96  | index | postgres | test96 public | idx_test97  | index | postgres | test97 public | idx_test98  | index | postgres | test98 public | idx_test99  | index | postgres | test99(128 rows)
生成测试脚本, 一个连接一次插入178条记录，占用2个32KB的block :
vi test.sql insert into test(crt_time) values (now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()),(now()); for ((i=1;i<=128;i++)) do sed "s/test/test$i/" test.sql > ./test$i.sql; done
开始测试前清除数据：
do language plpgsql $$  declarei int;sql text;begin  for i in 1..128 loop    sql := 'truncate test'||i;    execute sql;  end loop;end; $$;
测试方法：每轮测试插入12TB数据。通过以下方式控制：.1. 使用128个并行连接，每个连接执行1572864个事务。.2. 一共执行201326592个事务（每个事务插入178条记录）。.3. 一共插入35836133376条记录（358.36 亿记录）（共计12TB 数据，索引空间另算）。进行下一轮测试前，输出日志，并TRUNCATE所有的数据，然后重复以上测试。直到测试满24小时，输出统计数据。测试脚本如下 :
vi test.sh#!/bin/bashif [ $# -ne 5 ]; then  echo "please use: $0 ip port dbname user pwd"  exit 1fiIP=$1PORT=$2DBNAME=$3USER=$4PASSWord=$5export PGPASSWORD=$PASSWORDDEP_CMD="psql"which $DEP_CMD if [ $? -ne 0 ]; then  echo -e "dep commands: $DEP_CMD not exist."  exit 1fitruncate() {psql -h $IP -p $PORT -U $USER $DBNAME <<EOFdo language plpgsql /$/$  declarei int;sql text;begin  for i in 1..128 loop    sql := 'truncate test'||i;    execute sql;  end loop;end; /$/$;checkpoint;/qEOF}# truncate data firsttruncateSTART=`date +%s`echo "`date +%F%T` $START"for ((x=1;x>0;x++)) do # ------------------------------------------------------echo "Round $x test start: `date +%F%T` `date +%s`"for ((i=1;i<=128;i++)) do   pgbench -M prepared -n -r -f ./test$i.sql -h $IP -p $PORT -U $USER $DBNAME -c 1 -j 1 -t 1572864 >>./$i.log 2>&1 & done waitecho "Round $x test end: `date +%F%T` `date +%s`"# ------------------------------------------------------if [ $((`date +%s`-$START)) -gt 86400 ]; then  echo "end `date +%F%T` `date +%s`"  echo "duration second: $((`date +%s`-$START))"  exit 0fiecho "Round $x test end, start truncate `date +%F%T` `date +%s`"truncateecho "Round $x test end, end truncate `date +%F%T` `date +%s`"done
测试
nohup ./test.sh xxx.xxx.xxx.xxx 1921 postgres postgres postgres >./test.log 2>&1 &
测试结果
24小时完成12轮测试，平均每轮测试耗时7071秒。 506万行/s（每行360字节），1.78GB/s，全天插入4372亿，154TB数据。
查询性能
postgres=# select min(crt_time),max(crt_time) from test1;            min             |            max             ----------------------------+---------------------------- 2016-04-08 00:32:26.842728 | 2016-04-08 02:29:41.583367(1 row)postgres=# explain select count(*) from test1 where crt_time between '2016-04-08 00:32:00' and '2016-04-08 00:33:00';                                                                            QUERY PLAN                                                                             ------------------------------------------------------------------------------------------------------------------------------------------------------------------- Aggregate  (cost=1183919.81..1183919.82 rows=1 width=0)   ->  Bitmap Heap Scan on test1  (cost=14351.45..1180420.19 rows=1399849 width=0)         Recheck Cond: ((crt_time >= '2016-04-08 00:32:00'::timestamp without time zone) AND (crt_time <= '2016-04-08 00:33:00'::timestamp without time zone))         ->  Bitmap Index Scan on idx_test1  (cost=0.00..14001.49 rows=1399849 width=0)               Index Cond: ((crt_time >= '2016-04-08 00:32:00'::timestamp without time zone) AND (crt_time <= '2016-04-08 00:33:00'::timestamp without time zone))(5 rows)Time: 0.382 mspostgres=# select count(*) from test1 where crt_time between '2016-04-08 00:32:00' and '2016-04-08 00:33:00';  count  --------- 2857968(1 row)Time: 554.474 ms
小结
.1. 这个CASE主要的应用场景是实时的大数据入库，例如 物联网 的应用场景，大量的 传感器 会产生庞大的数据。又比如传统的 运营商网关 ，也会有非常庞大的流量数据或业务数据需要实时的入库。索引方面，用到了PostgreSQL黑科技BRIN。.2. 除了实时入库，用户如果需要流式实时处理，可以参考基于PostgreSQL的流式处理方案，
一天处理1万亿的实时流式处理是如何实现的？
https://yq.aliyun.com/articles/166
.3. 瓶颈, 还是在IO上面 , 有几个表现，TOP大量进程处于D(front io)状态 。
       w: S  --  Process Status          The status of the task which can be one of:             ’D’ = uninterruptible sleep             ’R’ = running             ’S’ = sleeping             ’T’ = traced or stopped             ’Z’ = zombie
所有块设备的使用率均达100% 。清理数据时 ：
Device:         rrqm/s   wrqm/s     r/s     w/s   rsec/s   wsec/s avgrq-sz avgqu-sz   await  svctm  %utildfa               0.00     0.00 5807.39 167576.65 1464080.93 1340613.23    16.18   535.69    3.02   0.01 116.77dfb               0.00     0.00 5975.10 185132.68 1506714.40 1481061.48    15.63   459.46    2.32   0.01 110.62dfc               0.00     0.00 5715.56 182584.05 1440771.98 1460672.37    15.41   568.02    2.93   0.01 112.37
插入数据时 ：
Device:         rrqm/s   wrqm/s     r/s     w/s   rsec/s   wsec/s avgrq-sz avgqu-sz   await  svctm  %utildfa               0.00     0.00    0.00 235936.00     0.00 1887488.00     8.00  2676.34   11.17   0.00  99.10dfb               0.00     0.00    0.00 237621.00     0.00 1900968.00     8.00    66.02    0.10   0.00  99.10dfc               0.00     0.00    0.00 239830.00     0.00 1918632.00     8.00    10.66    0.04   0.00 101.30
IO层面的性能问题，可以通过优化代码（例如 PostgreSQL bgwriter 在写出数据时，尽量顺序写出），便于OS层进行IO合并，来缓解IO压力，从这个信息来看，单次写IO的大小还可以再大点。
有几个工具你可能用得上，perf, systemtap, goprof.如果要较全面的分析，建议把PostgreSQL --enable-profiling打开用于诊断。