命令具体实现在redis-3.0/src/redis.c:genRedisInfoString。

Memory

Post author: ToRapture
Post link: <a href="https://torapture.github.io/2019/12/11/Redis%E7%AC%94%E8%AE%B0-info%E5%91%BD%E4%BB%A4/" title="Redis笔记 info命令">https://torapture.github.io/2019/12/11/Redis笔记-info命令/
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used_memory是redis通过在每次执行malloc和free等函数的时候维护定义在src/zmalloc.c中的used_memory变量实现的
used_memory_rss在linux中是通过读/proc/{pid}/stat这个文件的第24个字段rss得到number of pages the process in real memory然后再乘以sysconf(_SC_PAGESIZE)实现的。sysconf(_SC_PAGESIZE)表示Size of a page in bytes。
used_memory_peakRecord the max memory used since the server was started.
mem_fragmentation_ratioFragmentation = RSS / allocated-bytes，allocated-bytes即为used_memory

CPU