Post: Aligning IO on a hard disk RAID – the Benchmarks
…/mysql socket=/var/run/mysqld/mysqld.sock innodb_file_per_table = true innodb_data_file_path = ibdata1:…file_size = 10G myisam_repair_threads = 1 myisam_recover skip-grant-tables Amount of rows used...
View ArticleRecovery deleted ibdata1
Recently I had a case when a customer deleted the InnoDB main table space – ibdata1 – and redo logs – ib_logfile*.MySQL keeps InnoDB files open all the time. The following recovery technique is based...
View ArticleRecovery after DROP & CREATE
In a very popular data loss scenario a table is dropped and empty one is created with the same name. This is because mysqldump in many cases generates the “DROP TABLE” instruction before the “CREATE...
View ArticleHow to recover table structure from InnoDB dictionary
To recover a dropped or corrupt table with Percona Data Recovery Tool for InnoDB you need two things: media with records(ibdata1, *.ibd, disk image, etc.) and a table structure. Indeed, there is no...
View ArticleWhy is the ibdata1 file continuously growing in MySQL?
We receive this question about the ibdata1 file in MySQL very often in Percona Support.The panic starts when the monitoring server sends an alert about the storage of the MySQL server – saying that the...
View ArticleHow to move the InnoDB log sequence number (LSN) forward
This post focuses on the problem of the InnoDB log sequence number being in the future.Preface: What is an InnoDB log sequence number?The Log sequence number (LSN) is an important database parameter...
View ArticleIncremental backups with log archiving for XtraDB
Percona Server 5.6.11-60.3 has introduced a new feature called Log Archiving for XtraDB. This feature makes copies of the old log files before they are overwritten, thus saving all the redo log for a...
View ArticleExamining the TokuDB MySQL storage engine file structure
As we know different storage engines in MySQL have different file structures. Every table in MySQL 5.6 must have a .frm file in the database directory matching the table name. But where the rest of the...
View ArticleA closer look at the MySQL ibdata1 disk space issue and big tables
A recurring and very common customer issue seen here at the Percona Support team involves how to make the ibdata1 file “shrink” within MySQL. I can only imagine there’s a degree of regret by some of...
View ArticleWhen (and how) to move an InnoDB table outside the shared tablespace
In my last post, “A closer look at the MySQL ibdata1 disk space issue and big tables,” I looked at the growing ibdata1 problem under the perspective of having big tables residing inside the so-called...
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