Check whether redis is persistent
infoView persistence information
appendfsync has three options: always, everysec and no:
1. When selecting always, the server will force the contents of the AOF buffer every time an event is executed. Permanently written to the AOF file on the hard disk, it can be seen as recording this command in the AOF file every time you execute a redis write command. This ensures the integrity of data persistence, but the efficiency is the slowest, but It is also the safest; 2. If configured as everysec, every time the server performs a write operation (such as set, sadd, rpush), the command will be appended to the end of a separate AOF buffer, and Write the AOF buffer to the AOF file, and then perform file synchronization every second to actually write the AOF cache data in the memory buffer to the AOF file. This mode takes into account efficiency while ensuring data integrity. , even if the server is down, only the modifications made to the redis database within one second will be lost; 3. Configuring appendfsync to no means that you can accept the loss of the data in the redis database, and it will Append each write command to the end of the AOF buffer and then write it to the file. However, it is up to the system itself to decide when to perform file synchronization and actually write the data to the AOF file, that is, when the space in the memory buffer is filled or when The system automatically synchronizes after the set time limit. This mode is the fastest efficient, but it is also the most unsafe for the data. If the data in redis is taken out from the background database such as mysql, and it is data that can be retrieved at any time or is not important, then You can consider setting it to this mode.The above is the detailed content of Check whether redis is persistent. For more information, please follow other related articles on the PHP Chinese website!

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