showengineinnodbstatus的解读

如何查看innodb的相关信息

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BUFFER POOL AND MEMORY

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Total memory allocated 52873396224; in additional pool allocated 0

Dictionary memory allocated 720082

Buffer pool size 3145728

Free buffers 1033599

Database pages 1902184

Old database pages 702010

Modified db pages 398

Pending reads 0

Pending writes: LRU 0, flush list 0, single page 0

Pages made young 49894, not young 0

0.00 /s, 0.00 non-youngs/s

Pages read 139848, created 1762336, written 255420958

0.00 reads/s, 1.00 creates/s, 181.61 writes/s

Buffer pool hit rate 1000 / 1000, young-making rate 0 / 1000 not 0 / 1000

Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s

LRU len: 1902184, unzip_LRU len: 0

I/O sum[0]:cur[64], unzip sum[0]:cur[0]

Total memory allocated 393216; in additional pool allocated 0

INNODB分配的内存总量为52873396224字节，也就是49GB 额外内存池没有占用多余的空间

Dictionary memory allocated 720082

数据字典内存分配了720082字节

Buffer pool size 3145728

这是buffer pool数据页的数量 一共有3145728个（总内存是3145728*16/1024/1024/1024=4915200.25）

Free buffers 1033599

空闲页的数量 (1033599*16/1024=16149)

Database pages 1902184

Old list内的数据页数

Modified db pages 398

被修改的页数 ，脏页

Pending writes: LRU 0, flush list 0, single page 0

刷新页的数量，可以分为 LRU FLUSH single

Pages read 139848, created 1762336, written 255420958

页面的读取，创建，和刷新次数

Buffer pool hit rate 1000 / 1000

缓冲池命中率，命中率越高越好。这里的命中率是100%

Pending reads 0

正在读取的页的数量

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