-- 顯示innodb存儲引擎狀態(tài)的統(tǒng)計和配置信息
show engine innodb status;

展示的主要內(nèi)容有
-----------------
BACKGROUND THREAD  --后臺線程
-----------------
srv_master_thread loops: 19610306 srv_active, 0 srv_shutdown, 9705136 srv_idle  --統(tǒng)計Innodb啟動后的活動
srv_master_thread log flush and writes: 29312902  --寫入和刷新日志的次數(shù)
----------
SEMAPHORES  --信號量包含了線程等待互斥鎖或讀寫鎖的信息
----------
OS WAIT ARRAY INFO: reservation count 52795642  --os等待數(shù)組信息，分配插槽的次數(shù)
OS WAIT ARRAY INFO: signal count 57522728  --os等待數(shù)組信息，線程通過數(shù)組得到信號的次數(shù)
RW-shared spins 0, rounds 77349143, OS waits 9180114  --共享鎖期間，讀寫鎖存器上自旋等待個數(shù)，自旋循環(huán)迭代次數(shù)以及操作系統(tǒng)調(diào)用的等待個數(shù)
RW-excl spins 0, rounds 179767865, OS waits 2534243  --排他鎖期間，讀寫鎖存器上自旋等待個數(shù)，自旋循環(huán)迭代次數(shù)以及操作系統(tǒng)調(diào)用的等待個數(shù)
RW-sx spins 2068750, rounds 40171680, OS waits 844522  --共享排他鎖期間，讀寫鎖存器上自選等待個數(shù)，自旋循環(huán)迭代次數(shù)以及操作系統(tǒng)調(diào)用的等待個數(shù)
Spin rounds per wait: 77349143.00 RW-shared, 179767865.00 RW-excl, 19.42 RW-sx  --對于每一個互斥鎖，操作系統(tǒng)調(diào)用等待的每一個自旋循環(huán)迭代個數(shù)
------------
TRANSACTIONS --包含所有當前正在執(zhí)行的事務的信息
------------
Trx id counter 1888483436  --當前事務id
Purge done for trx s n:o < 1888483436 undo n:o < 0 state: running but idle --所有編號小于1888483436的事務都已經(jīng)從歷史記錄列表中清除了，清除舊的MVCC行時所用的事務id，這個值與當前事務ID進行比較，就可以知道有多少老版本的數(shù)據(jù)未被清除
History list length 17 --歷史列表的長度，位于Innodb數(shù)據(jù)文件的撤銷空間里的頁面的數(shù)目，如果事務執(zhí)行了更新并提交，該數(shù)目就會增加，當清理進程移除舊版本數(shù)據(jù)時，該數(shù)目會減少
LIST OF TRANSACTIONS FOR EACH SESSION: 當前事務列表
---TRANSACTION 422068961001072, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068960999248, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961005632, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961013840, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961012016, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961010192, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961001984, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961000160, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961017488, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961011104, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961012928, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961004720, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961002896, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961003808, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
---TRANSACTION 422068961007456, not started
0 lock struct(s), heap size 1136, 0 row lock(s)
--------
FILE I/O  --各種IO操作的Innodb內(nèi)部線程以及執(zhí)行了多少次IO操作
--------
-- 有四個線程
-- insert buffer thread 負責插入緩沖合并
-- log thread 負責異步刷日志
-- read thread 執(zhí)行預讀操作以嘗試預先讀取Innodb預感需要的數(shù)據(jù)
-- write thread 刷臟緩沖
I/O thread 0 state: waiting for completed aio requests (insert buffer thread) --IO線程的狀態(tài)
I/O thread 1 state: waiting for completed aio requests (log thread)
I/O thread 2 state: waiting for completed aio requests (read thread)
I/O thread 3 state: waiting for completed aio requests (read thread)
I/O thread 4 state: waiting for completed aio requests (read thread)
I/O thread 5 state: waiting for completed aio requests (read thread)
I/O thread 6 state: waiting for completed aio requests (write thread)
I/O thread 7 state: waiting for completed aio requests (write thread)
I/O thread 8 state: waiting for completed aio requests (write thread)
I/O thread 9 state: waiting for completed aio requests (write thread)
Pending normal aio reads: [0, 0, 0, 0] , aio writes: [0, 0, 0, 0] ,
 ibuf aio reads:, log i/o's:, sync i/o's:
Pending flushes (fsync) log: 0; buffer pool: 0 -- 掛起操作的信息，aio是指異步io
83934578288 OS file reads, 282688772 OS file writes, 190348192 OS fsyncs --innodb啟動后的總統(tǒng)計信息
984.40 reads/s, 16384 avg bytes/read, 10.15 writes/s, 9.12 fsyncs/s --最后一次顯示后的總統(tǒng)計信息
-------------------------------------
INSERT BUFFER AND ADAPTIVE HASH INDEX  --插入緩沖區(qū)與自適應散列統(tǒng)計信息
-------------------------------------
Ibuf: size 1, free list len 3078, seg size 3080, 8815726 merges --在頁中插入緩沖索引樹的當前大小，空閑列表的長度，在包含插入緩沖樹與頭信息的文件段中已分配頁的個數(shù)，被合并頁的個數(shù)
merged operations:
 insert 6898371, delete mark 38430046, delete 1226485  --通過類型區(qū)分，索引頁被執(zhí)行合并操作的次數(shù)
discarded operations:
 insert 1019, delete mark 0, delete 0 --無須合并丟棄操作的數(shù)量
Hash table size 34673, node heap has 1 buffer(s)
Hash table size 34673, node heap has 74 buffer(s)
Hash table size 34673, node heap has 1 buffer(s)
Hash table size 34673, node heap has 1 buffer(s)
Hash table size 34673, node heap has 1 buffer(s)
Hash table size 34673, node heap has 2 buffer(s)
Hash table size 34673, node heap has 28 buffer(s)
Hash table size 34673, node heap has 7 buffer(s)
5203.54 hash searches/s, 128.14 non-hash searches/s --成功使用自適應散列索引查找的數(shù)量，當不能使用自適應索引時向下搜索B樹的次數(shù)
---
LOG    --Innodb日志中活動信息
---
Log sequence number 319041331834 --當前日志序號
Log flushed up to   319041331699 -- 日志已經(jīng)刷到的位置
Pages flushed up to 319033170877 
Last checkpoint at  319033170877  -- 上一個檢查點，當前日志序列號LSN
0 pending log flushes, 0 pending chkp writes 
169033177 log i/o's done, 8.92 log i/o's/second --掛起的日志寫入次數(shù)，掛起的檢查點寫入個數(shù)，innodb啟動后的IO操作個數(shù)，從最近一次顯示之后的每秒IO操作個數(shù)
----------------------
BUFFER POOL AND MEMORY   --Innodb緩沖池與內(nèi)存使用情況
----------------------
Total large memory allocated 137428992 --分配的內(nèi)存
Dictionary memory allocated 1204989 --被數(shù)據(jù)字典表與索引對象所占空間的字節(jié)數(shù)
Buffer pool size   8191 --緩沖池個數(shù)
Free buffers       1024 --空閑緩沖區(qū)個數(shù)
Database pages     7052 --當前緩沖區(qū)LRU隊列的長度(分配用來存儲數(shù)據(jù)庫頁的頁數(shù))
Old database pages 2583 --舊的LRU隊列的長度
Modified db pages  530 --需要刷新的頁面的數(shù)量(臟數(shù)據(jù)庫頁數(shù))
Pending reads      0 --掛起讀操作的個數(shù)
Pending writes: LRU 0, flush list 0, single page 0 --通過LRU算法，等待刷新的頁數(shù)
Pages made young 983912385, not young 304833753259 --因為最近第一次被訪問時，變成新頁面的數(shù)目和沒有變成新頁面的數(shù)目
1.54 youngs/s, 16246.04 non-youngs/s -- 上述兩個值每秒的速率
Pages read 83934649301, created 4135172, written 103030852 --讀操作的頁面數(shù)目，在緩沖區(qū)中創(chuàng)建但是沒有讀取的頁面數(shù)目，寫操作的頁面數(shù)目
984.40 reads/s, 0.17 creates/s, 1.15 writes/s -- 上述值美妙的速率
Buffer pool hit rate 972 / 1000, young-making rate 0 / 1000 not 478 / 1000 --讀取到的頁面數(shù)與獲得的緩沖池頁面的比例，變?yōu)樾马撁娴捻撁鏀?shù)與獲得緩沖池頁面的比例，沒有變?yōu)樾马撁娴捻撁鏀?shù)與獲得緩沖池頁面的比例
Pages read ahead 913.79/s, evicted without access 5.60/s, Random read ahead 0.00/s --預讀的速率與不通過訪問剔除的預讀頁面的個數(shù)
LRU len: 7052, unzip_LRU len: 0 --LRU列表的長度，unzip_LRU列表的長度
I/O sum[4121]:cur[0], unzip sum[0]:cur[0] --IO操作的次數(shù)：當前間隔的IO
--------------
ROW OPERATIONS   --行操作
--------------
0 queries inside InnoDB, 0 queries in queue --當前有多少個正在執(zhí)行的查詢，在innodb_thread_concurrency隊列中的查詢個數(shù)
0 read views open inside InnoDB --只讀視圖的數(shù)量
Process ID=1543, Main thread ID=140593683990272, state: sleeping --線程id以及狀態(tài)
Number of rows inserted 56092883, updated 133093048, deleted 40729879, read 477150639699 --從innodb啟動后，插入、更新、刪除、讀取的行數(shù)
0.19 inserts/s, 7.73 updates/s, 0.00 deletes/s, 138100.85 reads/s -- 速率

-- 展示Innodb的互斥體信息
show engine innodb mutex;

Type      Name                           Status
InnoDB    rwlock: dict0dict.cc:2782       waits=4
InnoDB    rwlock: dict0dict.cc:1228       waits=80
InnoDB    rwlock: log0log.cc:846         waits=75
InnoDB    sum rwlock: buf0buf.cc:1460     waits=11

-- name列顯示了創(chuàng)建互斥體的源文件和行號
-- status列顯示了互斥體在操作系統(tǒng)上的等待次數(shù)

show status like 'innodb%log%'

Variable_name                 Value
Innodb_log_waits                0     日志文件太小時，操作必須等待日志刷新的等待時間計數(shù)器，該值如果長期大于0，可以適當增加日志文件大小
Innodb_log_write_requests      4539    日志寫入請求的數(shù)量
Innodb_log_writes               22     數(shù)據(jù)被寫入日志的次數(shù)
Innodb_os_log_fsyncs           1020   操作系統(tǒng)文件同步的數(shù)量(fsync()方法調(diào)用)
Innodb_os_log_pending_fsyncs    0     阻塞的文件同步請求的數(shù)量，如果該值開始增長并長期大于0，需要檢查磁盤訪問問題
Innodb_os_log_pending_writes    0     阻塞的日志寫請求的次數(shù)，如果該值開始增長并長期大于0，需要檢查磁盤訪問問題
Innodb_os_log_written         2855424  寫入日志中的字節(jié)總量
Innodb_available_undo_logs    128

-- 可以查看存儲引擎的統(tǒng)計信息，其中包含有緩沖池的信息
show engine innodb status;

截取出緩沖池的信息來進行分析
----------------------
BUFFER POOL AND MEMORY
----------------------
Total large memory allocated 137428992
Dictionary memory allocated 223164
Buffer pool size   8191
Free buffers       7374   空的且可用于緩沖數(shù)據(jù)的緩沖段個數(shù)
Database pages     809   
Old database pages 299
Modified db pages  0   發(fā)生變化的頁數(shù)
Pending reads      0   等待中的讀請求個數(shù)
Pending writes: LRU 0, flush list 0, single page 0
Pages made young 0, not young 0
0.00 youngs/s, 0.00 non-youngs/s
Pages read 503, created 306, written 2534
0.00 reads/s, 0.00 creates/s, 0.00 writes/s
No buffer pool page gets since the last printout
Pages read ahead 0.00/s, evicted without access 0.00/s, Random read ahead 0.00/s
LRU len: 809, unzip_LRU len: 0
I/O sum[0]:cur[0], unzip sum[0]:cur[0]

show status like 'innodb%buf%'
Variable_name                         Value
Innodb_buffer_pool_pages_data           809    含有數(shù)據(jù)的頁數(shù)，包括不變和改變的頁
Innodb_buffer_pool_bytes_data         13254656 含有數(shù)據(jù)的字節(jié)數(shù)
Innodb_buffer_pool_pages_dirty          0      改變的字節(jié)數(shù)
Innodb_buffer_pool_bytes_dirty          0      改變的頁的數(shù)目
Innodb_buffer_pool_pages_flushed       2525    緩沖池頁面被刷新的次數(shù)
Innodb_buffer_pool_pages_free           7374    空頁面的數(shù)目
Innodb_buffer_pool_pages_misc            8      用于管理工作的頁數(shù)，公式為'Innodb_buffer_pool_pages_total-Innodb_buffer_pool_pages_free-Innodb_buffer_pool_pages_data'
Innodb_buffer_pool_pages_total         8191    緩沖池中的總頁數(shù)
Innodb_buffer_pool_read_ahead_rnd        0      掃描大塊數(shù)據(jù)時發(fā)生隨機讀頭的數(shù)量
Innodb_buffer_pool_read_ahead            0      
Innodb_buffer_pool_read_ahead_evicted    0
Innodb_buffer_pool_read_requests      107632   邏輯讀請求的次數(shù)
Innodb_buffer_pool_reads                504    直接從磁盤中邏輯讀取的次數(shù)(沒有從緩沖池中讀)
Innodb_buffer_pool_wait_free             0     如果緩沖池繁忙且沒有空頁，innodb需要等待頁面刷新，該值表示等待次數(shù)，若始終大于0，可適當增加緩沖池大小
Innodb_buffer_pool_write_requests       47403   寫入innodb緩沖池的次數(shù)