MySQL kernel InnoDB Storage engine (Volume 1) notes, mysqlinnodb

MySQL kernel InnoDB Storage engine (Volume 1) notes, mysqlinnodb
MySQL kernel InnoDB Storage engine (Volume 1) Directory

• 1 Overview
• 2. Basic data structures and algorithms
• 3. Synchronization Mechanism
• 4. Redo logs
• 5mini-transaction (mtr)
• 6. Storage Management
• 7 records
• 8 index pages
• 9 lock
• 10B + Tree Index
• 11 Insert Buffer
• 12 Buffer Pool
• 13. Transaction Processing
• 14. Data Dictionary
• 15. Service Management

Overview of basic data structures and algorithm synchronization mechanisms

If 1000 cells in sync_primary_wait_array are allocated, ut_error triggers crash.

Redo log

LSN (indicates the number of bytes that the transaction writes to the redo log ?)

Checkpoint: refresh the pages in the buffer pool to the disk.

The redo log size is fixed (3 GB)-> archive log

Ib_logfile <N>

Redo log block (512B-12-8)

Redo log Group *

Group Submission: fsync-> log_flush_up_to copies the last log block.

Restore: recovery_from_checkpoint_start

Mini-transaction (mtr)

Force-Log-at-Commit

Mtr_t mtr; mtr_start (& mtr);... mtr_commit (& mtr );

MLOG_MULTI_REC_END

Storage Management

Segment (segment)

Tablespace

Data Structure: fil_system/space/node_struct

Four asynchronous I/O threads: asynchronous read, asynchronous write, insert cache, and redo log

Record

P103 VARCHAR type NULL does not occupy disk space, while char null is filled with 0x00

Large record: BLOB/TEXT (overflow page, extern attribute)

Logical record

Row record version (MVCC is only a column ?) : Using the hidden transaction ID column

The p114 function read_view_sees_trx_id is used to determine whether the current transaction can read the current version of the record. If not, row_sel_build_prev_vers_for_mysql

Index page

Page Directory (locate the location of the record on the Page)

Page Cursor *

Lock

Lock_rec_struct = {space, page_no, n_bits}

P144 LOCK_GAP (indicating that the range lock does not contain the endpoint)

Explicit and implicit locks ** (omitted)

Row lock maintenance * (emphasis, omitted)

Auto-increment lock (atomic ?)

Deadlock *

B + Tree Index

DML operations

Primary Key Update

Persistent cursor btr_pcur_struct

Adaptive hash Index *

Insert BufferBuffer Pool

Linear pre-read *

Logical pre-read

Page refresh

Transaction Processing

Undo log implementation: rollback segment + undo segment

Undo records

Purge *

Rollback

Commit

Data Dictionary Service Management
MySQL storage engine does not have InnoDB

Use
Mysql> show engines;
Command to see if there is InnoDB
If you do not mind reinstalling

What are the differences between the three storage engines of Mysql databases?

This is a matter of consideration for performance, as well as transaction support. You will know about Baidu.

MyISAM, InnoDB, Heap (Memory), NDB

Generally, InnoDB is used,

Mysql storage engines include MyISAM, InnoDB, BDB, MEMORY, MERGE, EXAMPLE, NDBCluster, ARCHIVE, CSV, BLACKHOLE, and FEDERATED. InnoDB and BDB provide transaction security tables, other storage engines are non-transaction security tables.
The two most commonly used storage engines:
1. Myisam is the default storage engine of Mysql. When create creates a new table without specifying the storage engine for the new table, Myisam is used by default. Each MyISAM is stored as three files on the disk. The file names are the same as the table names. The extensions are. frm (storage table definition),. MYD (MYData, storage data), and. MYI (MYIndex, storage index ). Data Files and index files can be placed in different directories, and I/O is evenly distributed for faster speed.
2. the InnoDB Storage engine provides transaction security with commit, rollback, and crash recovery capabilities. However, compared with the storage engine of Myisam, InnoDB writes less efficiently and occupies more disk space to retain data and indexes.

I don't know if it is helpful to you.