Redis configuration file append only file (AOF) section---data persistence

############################## only Append mode ###############################

#默认情况下Redis会异步的将数据导出到磁盘上. This pattern is sufficient for many applications,
#但是如果断电或者redis进程出问题就会导致一段时间内的更新数据丢失 (depending on the configuration item)
#
#这种只增文件是可选的能够提供更好的体验的数据持久化策略.
#举个例子, if the default configuration data Fsync policy is used, Redis loses only one second of the updated data in the event of an unexpected server power outage.
#或者当redis进程出问题但操作系统运转正常时, Redis will only lose one data update operation.
#
The #AOF and RDB persistence mode can be started at the same time without conflicts.
#如果AOF开启, aof files are loaded when Redis is started, and these files provide better assurance.
#请在 http://redis.io/topics/persistence For more data persistence information.

AppendOnly No

# only the file name of the file is added. (Default is Appendonly.aof)
# Appendfilename Appendonly.aof

The #调用fsync () function tells the operating system to actually write data to disk, rather than waiting for more data in the buffer.
#有些操作系统会将数据输出到磁盘, some operating systems are just ASAP.
#
#redis支持三种不同的方式:
#
#no: Do not call, wait for the operating system to empty the buffer when the operating system wants to output data. Soon.
# always: Each update data is written to only the add-in log file. Slow, but most secure.
# Everysec: Called once per second. Compromise.
#
#默认是每秒中一次, as it is often a compromise between speed and data security.
#如果你可以接受让操作系统去自动清空缓存, you can reduce this configuration to ' no ' (if you can accept data loss for a period of time, the default rdb is sufficient),
#这完全取决与你. If you want a better experience or use ' always ' from the opposite angle, it will be slow, but safer than ' everysec '.
#
#请在下面的文章中获取更多细节知识:
# http://antirez.com/post/redis-persistence-demystified.html
#
#如果你不是很清楚这三项之间的区别, or don't know which machine is right for you, just use the default.

# Appendfsync Always
Appendfsync always
# Appendfsync No

#当AOF策略设置为 ' always ' or ' everysec ', the background save process will perform many disk I/O operations,
The #在某些linux结构中redis会在调用sync () method is blocked for a long time. Remember, there is no way to solve this problem, even if it is called in a different process.
#
#使用如下配置可能会缓解这个问题, this will not call the Fsync () method in the main process when storing big data or bigrewriteaof.
#
# This means that if another child process is doing a save operation, Redis behaves as if it were configured as ' Appendfsync no '.
#在实际应用中, this means that in the worst scenario (using the Linux default configuration) a 30-second log may be lost.
#
#如果你有特殊的情况可以配置为 ' yes '. But configured as ' no ' is the safest option.
No-appendfsync-on-rewrite No


#自动重写只增文件.
#redis可以自动盲从的调用 ' bgrewriteaof ' to rewrite the log file if the log file grows by a specified percentage.
#
#它是这样工作的: Redis logs the size of the log file after each rewrite. (The log file size is the default if no rewritten size after reboot)
#
# This benchmark log size is compared with the current log size. If the current size is greater than the specified percentage, the override mechanism is triggered.
#同时, you also have to develop a rewrite downline to avoid the growth percentage enough, but the log file is still small.
#
#指定百分比为0可以注掉自动重写日志文件功能.

Auto-aof-rewrite-percentage 100
Auto-aof-rewrite-min-size 64MB

Redis configuration file append only file (AOF) section---data persistence