Emergency

Search Results for: myISAM table locking

mydumper [less] locking

In this post I would like to review how my dumper for MySQL works from the point of view of locks. Since 0.6 serie we have different options, so I will try to explain how …

Read More
 

Innodb Table Locks

Innodb uses row level locks right ? So if you see locked tables reported in SHOW ENGINE INNODB STATUS you might be confused and rightfully so as Innodb table locking is a bit more complicated …

Read More
 

How FLUSH TABLES WITH READ LOCK works with Innodb Tables

Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only …

Read More
 

Impossible – possible, moving InnoDB tables between servers

This is probably the feature I missed most from early days when I started to use InnoDB instead of MyISAM. Since that I figured out how to survive without it, but this is first question …

Read More
 

Concurrent inserts on MyISAM and the binary log

Recently I had an interesting surprise with concurrent inserts into a MyISAM table. The inserts were not happening concurrently with SELECT statements; they were blocking and the process list was filling up with queries in …

Read More
 

MyISAM Scalability and Innodb, Falcon Benchmarks

We many times wrote about InnoDB scalability problems, this time We are faced with one for MyISAM tables. We saw that several times in synthetic benchmarks but never in production, that’s why we did not …

Read More
 

MySQL MyISAM Active Active Clustering – looking for trouble ?

Reading last few days worth of planet MySQL and commenting on some entries as you can see. The post by Oli catches my attention. There is also PDF with more details available Oli is saying …

Read More
 

Opening Tables scalability

I was restarting MySQL on box with 50.000 of Innodb tables and again it took couple of hours to reach decent performance because of “Opening Tables” stage was taking long. Part of the problem is …

Read More
 

INSERT INTO … SELECT Performance with Innodb tables.

Everyone using Innodb tables probably got use to the fact Innodb tables perform non locking reads, meaning unless you use some modifiers such as LOCK IN SHARE MODE or FOR UPDATE, SELECT statements will not …

Read More
 

ObjectRocket’s David Murphy talks about MongoDB, Percona Live Amsterdam

Say hello to David Murphy, lead DBA and MongoDB Master at ObjectRocket (a Rackspace company). David works on sharding, tool building, very large-scale issues and high-performance MongoDB architecture. Prior to ObjectRocket he was a MySQL/NoSQL …

Read More