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Displaying posts with tag: Internals (reset)

TokuDB benchmark on PCIe
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MariaDB TokuDB benchmark on FusionIO ,Compare TokuDB and InnoDB engines.

read: TokuDB_benchmark

MySQL lost “AUTO_INCREMENT” after a long time
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I create a empty table and then alter this table's "AUTO_INCREMENT" starts from 10000000.After a long time ,MySQL lost "AUTO_INCREMENT" definition when I show this table again. MariaDB has the same problem but Percona Server is fine.


Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 141028725
Server version: 5.6.17-log MySQL Community Server (GPL)

Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights …
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NVMFS Supports Atomic Writes
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Benchmark for NVMFS (supports atomic writes ,so we can close double-write option on specific MySQL version )

tips: some Flash-based cards could support large block map , the main idea is to avoid fractured page writes.

[Reprint]Injection MySQL – Function
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Reprint a PDF for MySQL Injection Test

MySQL Error Based SQL Injection Using EXP

What Makes the MySQL Audit Plugin API Special?
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Why Should I Be Reading This?

To better understand how the MySQL Server functions, how to monitor the relevant server events, and find out what’s new in MySQL 5.7.8.

What’s Special About the Audit Plugin API?

Picking the right API for your new plugin is probably the most important design decision a plugin author will need to make.…

How to configure Tcpdump system
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MySQL Tcpdump system : use percona-toolkit to analyze network packages

We can identify problem SQLs with high execution frequency.

With DBMON system and AWR system we can find problem SQLs in a special time (high frequency, occurs over a period of time)

View this PDF:

The InnoDB Change Buffer
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One of the challenges in storage engine design is random I/O during a write operation. In InnoDB, a table will have one clustered index and zero or more secondary indexes.  Each of these indexes is a B-tree.  When a record is inserted into a table, the record is first inserted into clustered index and then into each of the secondary indexes.  So, the resulting I/O operation will be randomly distributed across the disk.  The I/O pattern is similarly random for update and delete operations. To mitigate this problem, the InnoDB storage engine uses a special data structure called the …

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MariaDB : Bug when add index on Partition table
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Version: 5.5.5-10.0.10-MariaDB-log MariaDB Server

When I use mariadb as multi-source slave DB I met a strange problem . Creating index on a vary large partition table , Mariadb do — copy to tmp table on the slave side. It takes a long time and still not finish over 9 hours.

Primary : MySQL 5.6.16 —

add index on a partition table:

CREATE TABLE `track_raw_wap211_log` (
 `table_id` varchar(100) DEFAULT NULL,
 `page_id` varchar(100) DEFAULT NULL,
 `banner_id` varchar(100) DEFAULT NULL,
 `button_id` varchar(100) DEFAULT NULL, …
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Performance Impact of InnoDB Transaction Isolation Modes in MySQL 5.7
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During the process of reviewing our server defaults for MySQL 5.7, we thought that it might be better to change the default transaction isolation level from REPEATABLE-READ to READ-COMMITTED (the default for PostgreSQL, Oracle, and SQL Server). After some benchmarking, however, it seems that we should stick with REPEATABLE-READ as the default for now.

It’s very easy to …

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Extent Descriptor Page of InnoDB
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Within the MySQL data directory, the InnoDB storage engine creates two types of files — the data files and the redo log files. Each data file (or ibd file) belongs to exactly one tablespace. Each tablespace is given a unique identifier called the space_id. One tablespace can have 1 or more data files. If a tablespace has more than one data file, then the data files have a specific order or sequence. The data files can be thought of as being concatenated to each other in that specific order.

The data file is made up of a …

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Showing entries 1 to 10 of 28 10 Older Entries

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