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Wednesday 11 May 2016

数据库SSDB基础

前言

ssdb 是一个高性能支持丰富数据结构的 NoSQL 数据库, 用于替代 Redis.
它与Redis相比，具备明显优势的一个特性就是基于硬盘存储，所以它支撑的数据量不会因为内存的限制而受约束。
至于性能，由于存取效率一部分取决于硬盘的IOPS，所以官网给的benchmark结果应该是极高IOPS的硬盘(比如固态硬盘)上测试出的结果，有人在正常环境下做过测试，实际效率是redis的42%~57%，CPU负载要高出一倍，并发效率也与redis有明显差距，详细可以参考 redis和ssdb读取性能对比
虽然SSDB效率上不如REDIS,但基于磁盘存储有着其最大的优势,毕竟很多业务数据远超过服务器内存的容量，即便不超过，相较硬盘，内存也要贵很多，所以时间与空间的取舍就取决于具体的应用场景了
下面分享一下 ssdb 的基本操作，详细可以参阅官方文档

Tip: 目前官方版本是 SSDB 1.9.2

概要

下载和安装

使用下面的方法进行安装

wget --no-check-certificate https://github.com/ideawu/ssdb/archive/master.zip
unzip master
cd ssdb-master
make
sudo make install

安装过程

[root@h101 src]# wget --no-check-certificate https://github.com/ideawu/ssdb/archive/master.zip
--2015-11-24 19:36:34--  https://github.com/ideawu/ssdb/archive/master.zip
Resolving github.com... 192.30.252.130
Connecting to github.com|192.30.252.130|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://codeload.github.com/ideawu/ssdb/zip/master [following]
--2015-11-24 19:36:35--  https://codeload.github.com/ideawu/ssdb/zip/master
Resolving codeload.github.com... 192.30.252.147
Connecting to codeload.github.com|192.30.252.147|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [application/zip]
Saving to: “master.zip”

    [                                                                                                     <=>

2015-11-24 19:37:19 (33.7 KB/s) - “master.zip” saved [1460288]

[root@h101 src]# ll master.zip 
-rw-r--r-- 1 root root 1460288 Nov 24 19:37 master.zip
[root@h101 src]# 
[root@h101 src]# unzip master.zip 
Archive:  master.zip
9497637f54da00f364e310de42000284545cfebe
   creating: ssdb-master/
  inflating: ssdb-master/.gitignore  
  inflating: ssdb-master/ChangeLog   
  inflating: ssdb-master/Dockerfile  
  inflating: ssdb-master/LICENSE     
  inflating: ssdb-master/Makefile    
  inflating: ssdb-master/README.md 
...
...
   creating: ssdb-master/tools/ssdb_cli/
  inflating: ssdb-master/tools/ssdb_cli/cluster.cpy  
  inflating: ssdb-master/tools/ssdb_cli/exporter.cpy  
  inflating: ssdb-master/tools/ssdb_cli/flushdb.cpy  
  inflating: ssdb-master/tools/ssdb_cli/importer.cpy  
  inflating: ssdb-master/tools/ssdb_cli/util.cpy  
  inflating: ssdb-master/tools/unittest.php  
 extracting: ssdb-master/version     
[root@h101 src]# 
[root@h101 src]# ll ssdb-master/
total 4912
drwxr-xr-x 6 root root    4096 Nov 23 20:34 api
-rw-r--r-- 1 root root     671 Nov 24 19:41 build_config.mk
-rwxr-xr-x 1 root root    3468 Nov 23 20:34 build.sh
-rw-r--r-- 1 root root    4831 Nov 23 20:34 ChangeLog
drwxr-xr-x 6 root root    4096 Nov 23 20:34 deps
-rw-r--r-- 1 root root     971 Nov 23 20:34 Dockerfile
drwxr-xr-x 2 root root    4096 Nov 23 20:34 docs
-rw-r--r-- 1 root root    1470 Nov 23 20:34 LICENSE
-rw-r--r-- 1 root root    1573 Nov 23 20:34 Makefile
-rw-r--r-- 1 root root    4412 Nov 23 20:34 README.md
drwxr-xr-x 6 root root    4096 Nov 24 19:41 src
-rwxr-xr-x 1 root root     946 Nov 23 20:34 ssdb.conf
-rwxr-xr-x 1 root root 4950089 Nov 24 19:40 ssdb-server
-rwxr-xr-x 1 root root     705 Nov 23 20:34 ssdb_slave.conf
drwxr-xr-x 3 root root    4096 Nov 24 19:40 tools
drwxr-xr-x 2 root root    4096 Nov 24 19:40 var
drwxr-xr-x 2 root root    4096 Nov 24 19:40 var_slave
-rw-r--r-- 1 root root       6 Nov 23 20:34 version
[root@h101 src]# 
[root@h101 src]# cd ssdb-master/
[root@h101 ssdb-master]# make 

##### building snappy... #####
checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /bin/mkdir -p
checking for gawk... gawk
...
...
g++ -o ssdb-repair ssdb-repair.o ../src/net/link.o ../src/net/fde.o ../src/util/log.o ../src/util/bytes.o   --1.18/libleveldb.a" "/usr/local/src/ssdb-master/deps/snappy-1.1.0/.libs/libsnappy.a" "/usr/local/src/ssdb-mas
g++ -o leveldb-import leveldb-import.o ../src/net/link.o ../src/net/fde.o ../src/util/log.o ../src/util/byteseveldb-1.18/libleveldb.a" "/usr/local/src/ssdb-master/deps/snappy-1.1.0/.libs/libsnappy.a" "/usr/local/src/ss
g++ -o ssdb-migrate ssdb-migrate.o ../api/cpp/libssdb-client.a ../src/util/libutil.a
make[1]: Leaving directory `/usr/local/src/ssdb-master/tools'
[root@h101 ssdb-master]# echo $?
0
[root@h101 ssdb-master]# make install 
mkdir -p /usr/local/ssdb
mkdir -p /usr/local/ssdb/_cpy_
mkdir -p /usr/local/ssdb/deps
mkdir -p /usr/local/ssdb/var
mkdir -p /usr/local/ssdb/var_slave
cp -f ssdb-server ssdb.conf ssdb_slave.conf /usr/local/ssdb
cp -rf api /usr/local/ssdb
cp -rf \
  tools/ssdb-bench \
  tools/ssdb-cli tools/ssdb_cli \
  tools/ssdb-cli.cpy tools/ssdb-dump \
  tools/ssdb-repair \
  /usr/local/ssdb
cp -rf deps/cpy /usr/local/ssdb/deps
chmod 755 /usr/local/ssdb
chmod -R ugo+rw /usr/local/ssdb/*
rm -f /usr/local/ssdb/Makefile
[root@h101 ssdb-master]#

默认将安装在 /usr/local/ssdb 目录下

[root@h101 ssdb-master]# ll /usr/local/ssdb/
total 17848
drwxrwxrwx 6 root root    4096 Nov 24 19:41 api
drwxrwxrwx 2 root root    4096 Nov 24 19:41 _cpy_
drwxrwxrwx 3 root root    4096 Nov 24 19:41 deps
-rwxrwxrwx 1 root root 4186529 Nov 24 19:41 ssdb-bench
drwxrwxrwx 2 root root    4096 Nov 24 19:41 ssdb_cli
-rwxrwxrwx 1 root root     149 Nov 24 19:41 ssdb-cli
-rwxrwxrwx 1 root root   12560 Nov 24 19:41 ssdb-cli.cpy
-rwxrwxrwx 1 root root     946 Nov 24 19:41 ssdb.conf
-rwxrwxrwx 1 root root 4531101 Nov 24 19:41 ssdb-dump
-rwxrwxrwx 1 root root 4546317 Nov 24 19:41 ssdb-repair
-rwxrwxrwx 1 root root 4950089 Nov 24 19:41 ssdb-server
-rwxrwxrwx 1 root root     705 Nov 24 19:41 ssdb_slave.conf
drwxrwxrwx 2 root root    4096 Nov 24 19:41 var
drwxrwxrwx 2 root root    4096 Nov 24 19:41 var_slave
[root@h101 ssdb-master]#

启动和停止

前台运行

这种模式下会占用当前的terminal

[root@h101 ssdb]# ./ssdb-server  ssdb.conf 
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

查看进程状态

[root@h101 ssdb]# ps faux | grep ssdb | grep -v grep 
root     10734  0.4  1.8 184860 34508 pts/1    Sl+  20:29   0:07          \_ ./ssdb-server ssdb.conf
[root@h101 ssdb]#

查看日志

[root@h101 ssdb]# cat log.txt 
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(46): ssdb-server 1.9.2
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(47): conf_file        : ssdb.conf
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(48): log_level        : debug
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(49): log_output       : log.txt
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(50): log_rotate_size  : 1000000000
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(52): main_db          : ./var/data
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(53): meta_db          : ./var/meta
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(54): cache_size       : 500 MB
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(55): block_size       : 32 KB
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(56): write_buffer     : 64 MB
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(57): max_open_files   : 500
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(58): compaction_speed : 1000 MB/s
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(59): compression      : yes
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(60): binlog           : yes
2015-11-24 20:29:21.692 [INFO ] ssdb-server.cpp(61): sync_speed       : -1 MB/s
2015-11-24 20:29:21.719 [INFO ] binlog.cpp(175): binlogs capacity: 20000000, min: 0, max: 0,
2015-11-24 20:29:21.729 [INFO ] server.cpp(159): server listen on 127.0.0.1:8888
2015-11-24 20:29:21.729 [INFO ] server.cpp(169): auth: off
2015-11-24 20:29:21.730 [DEBUG] cluster.cpp(13): Cluster init
2015-11-24 20:29:21.730 [INFO ] serv.cpp(329): key_range.kv: "", ""
2015-11-24 20:29:21.730 [INFO ] ssdb-server.cpp(84): pidfile: ./var/ssdb.pid, pid: 10734
2015-11-24 20:29:21.730 [INFO ] ssdb-server.cpp(85): ssdb server started.
2015-11-24 20:29:21.731 [DEBUG] ttl.cpp(112): load 0 keys into fast_keys
2015-11-24 20:29:21.732 [DEBUG] worker.cpp(17): writer 0 init
2015-11-24 20:29:21.732 [DEBUG] worker.cpp(17): reader 0 init
2015-11-24 20:29:21.733 [DEBUG] worker.cpp(17): reader 1 init
2015-11-24 20:29:21.741 [DEBUG] worker.cpp(17): reader 2 init
2015-11-24 20:29:21.742 [DEBUG] worker.cpp(17): reader 3 init
2015-11-24 20:29:21.758 [DEBUG] worker.cpp(17): reader 4 init
2015-11-24 20:29:21.775 [DEBUG] worker.cpp(17): reader 5 init
2015-11-24 20:29:21.794 [DEBUG] worker.cpp(17): reader 6 init
2015-11-24 20:29:21.810 [DEBUG] worker.cpp(17): reader 7 init
2015-11-24 20:29:21.810 [DEBUG] worker.cpp(17): reader 9 init
2015-11-24 20:29:21.811 [DEBUG] worker.cpp(17): reader 8 init
2015-11-24 20:34:22.630 [INFO ] server.cpp(203): server running, links: 0
2015-11-24 20:39:22.630 [INFO ] server.cpp(203): server running, links: 0
2015-11-24 20:44:22.630 [INFO ] server.cpp(203): server running, links: 0
2015-11-24 20:49:22.630 [INFO ] server.cpp(203): server running, links: 0
2015-11-24 20:54:22.630 [INFO ] server.cpp(203): server running, links: 0
2015-11-24 20:59:22.630 [INFO ] server.cpp(203): server running, links: 0
[root@h101 ssdb]#

查看线程

[root@h101 ssdb]# pstree -a 10734
ssdb-server ssdb.conf
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  ├─{ssdb-server}
  └─{ssdb-server}
[root@h101 ssdb]# ps -Lf 10734 
UID        PID  PPID   LWP  C NLWP STIME TTY      STAT   TIME CMD
root     10734 10446 10734  0   14 20:29 pts/1    Sl+    0:01 ./ssdb-server ssdb.conf
root     10734 10446 10735  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10736  0   14 20:29 pts/1    Sl+    0:06 ./ssdb-server ssdb.conf
root     10734 10446 10737  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10738  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10739  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10740  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10741  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10742  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10743  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10744  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10745  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10746  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
root     10734 10446 10747  0   14 20:29 pts/1    Sl+    0:00 ./ssdb-server ssdb.conf
[root@h101 ssdb]#

停止服务

[root@h101 ssdb]# ./ssdb-server  ssdb.conf  -s stop 
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

[root@h101 ssdb]# ps faux | grep ssdb | grep -v grep 
[root@h101 ssdb]#

后台运行

这种方式不会占用当前terminal，关闭当前terminal也不会导致服务退出

[root@h101 ssdb]# ./ssdb-server  -d ssdb.conf 
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

[root@h101 ssdb]# ps faux | grep ssdb | grep -v grep 
root     10890  1.7  1.8 184860 36164 ?        Ssl  21:05   0:00 ./ssdb-server -d ssdb.conf
[root@h101 ssdb]# pstree 10890
ssdb-server───13*[{ssdb-server}]
[root@h101 ssdb]#

客户端连接

[root@h101 ssdb]# ./ssdb-cli -p 8888
ssdb (cli) - ssdb command line tool.
Copyright (c) 2012-2015 ssdb.io

'h' or 'help' for help, 'q' to quit.

ssdb-server 1.9.2

ssdb 127.0.0.1:8888> info 
version
 1.9.2
links
 1
total_calls
 1
dbsize
 0
binlogs
     capacity : 20000000
     min_seq  : 0
     max_seq  : 0
serv_key_range
     kv  : "" - ""
     hash: "" - ""
     zset: "" - ""
     list: "" - ""
data_key_range
     kv  : "" - ""
     hash: "" - ""
     zset: "" - ""
     list: "" - ""
leveldb.stats
                                Compactions
 Level  Files Size(MB) Time(sec) Read(MB) Write(MB)
 --------------------------------------------------
 
17 result(s) (0.001 sec)
ssdb 127.0.0.1:8888>

发送信号终止服务

[root@h101 ssdb]# ps faux | grep ssdb | grep -v grep 
root     10890  0.4  1.8 184860 36164 ?        Ssl  21:05   0:01 ./ssdb-server -d ssdb.conf
[root@h101 ssdb]# cat var/ssdb.pid 
10890[root@h101 ssdb]# kill `cat ./var/ssdb.pid`
[root@h101 ssdb]# ps faux | grep ssdb | grep -v grep 
[root@h101 ssdb]# cat var/ssdb.pid
cat: var/ssdb.pid: No such file or directory
[root@h101 ssdb]#

SSDB 启动脚本

修改 configs 配置，使其指向正确的位置

[root@h101 tools]# cp /usr/local/src/ssdb-master/tools/ssdb.sh  /etc/init.d/ssdb
[root@h101 tools]# vim ssdb.sh 
[root@h101 tools]# grep configs=  /etc/init.d/ssdb
# configs="/data/ssdb_data/test/ssdb.conf /data/ssdb_data/test2/ssdb.conf"
#configs="/data/ssdb_data/test/ssdb.conf"
configs="/usr/local/ssdb/ssdb.conf"
[root@h101 tools]#

使用脚本启动服务

[root@h101 ~]# /etc/init.d/ssdb  start 
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

[root@h101 ~]# ps faux | grep ssdb | grep -v grep 
root      2795  2.6  1.8 184864 36180 ?        Ssl  09:41   0:00 /usr/local/ssdb/ssdb-server /usr/local/ssdb/ssdb.conf -s restart -d
[root@h101 ~]# /etc/init.d/ssdb  stop 
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

[root@h101 ~]# ps faux | grep ssdb | grep -v grep 
[root@h101 ~]#

SSDB相关配置可以参阅SSDB配置
SSDB相关命令可以参阅SSDB命令

master-master

config on h101

[root@h101 ~]# grep -v "#" /etc/ssdb/ssdb1234.conf 

work_dir = /data/ssdb/ssdb1234
pidfile = /data/ssdb/ssdb1234/ssdb.pid

server:
 port: 1234
 ip: 0.0.0.0
 deny: all
 allow: 127.0.0.1
 allow: 192.168

replication:
 binlog: yes
 sync_speed: -1
 slaveof:
  id: svc_h102_1
  type: mirror
  host: h102
  port: 1234

logger:
 level: debug
 output: /data/ssdb/ssdb1234/log.txt
 rotate:
  size: 1000000000

leveldb:
 cache_size: 500
 block_size: 32
 write_buffer_size: 64
 compaction_speed: 1000
 compression: yes


[root@h101 ~]#

config on h102

[root@h102 ssdb]# grep -v "#" /etc/ssdb/ssdb1234.conf 
work_dir = /data/ssdb/ssdb1234
pidfile = /data/ssdb/ssdb1234/ssdb.pid

server:
 port: 1234
 ip: 0.0.0.0
 deny: all
 allow: 127.0.0.1
 allow: 192.168

replication:
 binlog: yes
 sync_speed: -1
 slaveof:
  id: svc_h101_1
  type: mirror
  host: h101
  port: 1234

logger:
 level: debug
 output: /data/ssdb/ssdb1234/log.txt
 rotate:
  size: 1000000000

leveldb:
 cache_size: 500
 block_size: 32
 write_buffer_size: 64
 compaction_speed: 1000
 compression: yes
[root@h102 ssdb]#

Note: 注意以下几点

1 . 注意防火墙的影响
2 . slaveof.id 是 master的id ，这是从 slave角度来看的, 不要在 master 上配置它自己的id.
3 . 对于新版本(1.9.2+), slaveof.ip 改成了 slaveof.host 用来指定 master 的主机名(域名)
4 . type设定为 mirror ，默认情况下是sync

分别启动服务

[root@h101 ~]# /usr/local/ssdb/ssdb-server -d /etc/ssdb/ssdb1234.conf
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

[root@h101 ~]# 
----------
[root@h102 ~]# /usr/local/ssdb/ssdb-server -d /etc/ssdb/ssdb1234.conf
ssdb-server 1.9.2
Copyright (c) 2012-2015 ssdb.io

[root@h102 ~]#

分别查看状态

ssdb h101:1234> info 
version
 1.9.2
links
 1
total_calls
 10
dbsize
 240
binlogs
     capacity : 20000000
     min_seq  : 1
     max_seq  : 7
replication
 client 192.168.100.102:38671
     type     : mirror
     status   : SYNC
     last_seq : 7
replication
 slaveof h102:1234
     id         : svc_h102_1
     type       : mirror
     status     : SYNC
     last_seq   : 9
     copy_count : 0
     sync_count : 4
serv_key_range
     kv  : "" - ""
     hash: "" - ""
     zset: "" - ""
     list: "" - ""
data_key_range
     kv  : "1" - "z"
     hash: "" - ""
     zset: "" - ""
     list: "" - ""
leveldb.stats
                                Compactions
 Level  Files Size(MB) Time(sec) Read(MB) Write(MB)
 --------------------------------------------------
   0        1        0         0        0         0
 
21 result(s) (0.001 sec)
ssdb h101:1234> 
----------
ssdb h102:1234> info 
version
 1.9.2
links
 1
total_calls
 12
dbsize
 234
binlogs
     capacity : 20000000
     min_seq  : 3
     max_seq  : 9
replication
 client 192.168.100.101:43355
     type     : mirror
     status   : SYNC
     last_seq : 9
replication
 slaveof h101:1234
     id         : svc_h101_1
     type       : mirror
     status     : SYNC
     last_seq   : 7
     copy_count : 0
     sync_count : 1
serv_key_range
     kv  : "" - ""
     hash: "" - ""
     zset: "" - ""
     list: "" - ""
data_key_range
     kv  : "1" - "z"
     hash: "" - ""
     zset: "" - ""
     list: "" - ""
leveldb.stats
                                Compactions
 Level  Files Size(MB) Time(sec) Read(MB) Write(MB)
 --------------------------------------------------
   1        1        0         0        0         0
 
21 result(s) (0.001 sec)
ssdb h102:1234>

详细可以参考同步和复制的配置与监控

限制

Item	Comment
最大 Key 长度	200 字节
最大 Value 长度	31MB
最大请求或响应长度	31MB
单个 HASH 中的元素数量	9,223,372,036,854,775,807
单个 ZSET 中的元素数量	9,223,372,036,854,775,807
单个 QUEUE 中的元素数量	9,223,372,036,854,775,807
命令最多参数个数	所有参数加起来体积不超过 31MB 大小

内存占用

一个 ssdb-server 实例占用的内存瞬时(有可能, 而且即使达到, 也只是持续短时间)最高达到(MB):
对于压缩选项没有开启的情况

cache_size + write_buffer_size * 66 + 32

如果压缩选项开启 (compression: yes) , 计算公式是:

cache_size + 10 * write_buffer_size * 66 + 32

可以调整配置参数, 限制 ssdb-server 的内存占用.

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