MySQL - bufferpool related information

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One 、 see InnoDB Store some status information during the running process of the engine

SHOW ENGINE INNODB STATUS;

202207200851SHOW ENGINE INNODB STATUS（ All ）.txt
202207200851SHOW ENGINE INNODB STATUS（BufferPool Related information ）.txt

Two 、BufferPool Related information

26826768384B = 24.984375GB
25766658048B = 23.9970703GB

----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 26826768384
Dictionary memory allocated 156608199
Internal hash tables (constant factor + variable factor)
    Adaptive hash index 1038461120 	(407954752 + 630506368)
    Page hash           3187928 (buffer pool 0 only)
    Dictionary cache    258596887 	(101988688 + 156608199)
    File system         9986392 	(812272 + 9174120)
    Lock system         63778552 	(63750152 + 28400)
    Recovery system     0 	(0 + 0)
Buffer pool size   1572672
Buffer pool size, bytes 25766658048
Free buffers       32768
Database pages     1501423
Old database pages 554072
Modified db pages  0
Pending reads      0
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 509913737, not young 16908464306
0.00 youngs/s, 0.00 non-youngs/s
Pages read 834246715, created 30683415, written 249886514
0.00 reads/s, 0.00 creates/s, 0.75 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: 1501423, unzip_LRU len: 0
I/O sum[72]:cur[0], unzip sum[0]:cur[0]
----------------------

Parameters	describe
Total large memory allocated	BufferPool The amount of contiguous memory space requested from the operating system
Dictionary memory allocated	Memory space size of data dictionary （ and BufferPool It doesn't matter. ）
Buffer pool size	BufferPool How many buffer pages can be accommodated
Free buffers	BufferPool How many free buffer pages are there （free How many nodes are there in the linked list ）
Database pages	LRU The number of pages in the linked list , contain young and old The number of nodes in the two regions
Old database pages	LRU Linked list old The number of nodes in the area
Modified db pages	Number of dirty pages （flush The number of nodes in the linked list ）
Pending reads	Wait to load from disk to BufferPool Number of pages in
Pending writes	Wait for BufferPool Number of pages refreshed to disk LRU： from LUR The number of pages refreshed to disk in the linked list flush list： from flush The number of pages refreshed to disk in the linked list single page： The number of pages refreshed to disk in the form of a single page
Pages made young	LRU In the linked list, once from old Area moved to young The number of nodes in the area header
Pages made not young
youngs/s	Every second from old Area moved to young The number of nodes in the area header
non-youngs/s	Because the time per second does not meet the time limit, it cannot be from old Area moved to young The number of nodes in the area header
Pages read	Number of pages read
Pages created	Number of pages created
Pages written	Number of pages written
Buffer pool hit rate	It means that in a certain period of time in the past , Average access 1000 Second page , How many times has this page been cached to BufferPool in
young-making rate	It means that in a certain period of time in the past , Average access 1000 Second page , How many visits have made the page move to young The head of the area
not（young-making rate）	It means that in a certain period of time in the past , Average access 1000 Second page , How many visits did not move the page to young The head of the area
LRU len	LRU The number of nodes in the linked list
unzip_LRU len	unzip_LRU The number of nodes in the linked list
I/O sum	lately 50s Total number of disk pages read
I/O cur	The number of disk pages being read now
I/O unzip sum	lately 50s Number of pages decompressed
I/O unzip cur	The number of files being decompressed