November 22, 2014

Building Indexes by Sorting In Innodb (AKA Fast Index Creation)

Innodb can indexes built by sort since Innodb Plugin for MySQL 5.1 which is a lot faster than building them through insertion, especially for tables much larger than memory and large uncorrelated indexes you might be looking at 10x difference or more. Yet for some reason Innodb team has chosen to use very small (just […]

Improved InnoDB fast index creation

One of the serious limitations in the fast index creation feature introduced in the InnoDB plugin is that it only works when indexes are explicitly created using ALTER TABLE or CREATE INDEX. Peter has already blogged about it before, here I’ll just briefly reiterate other cases that might benefit from that feature: when ALTER TABLE […]

When (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 shared tablespace. In the particular case that motivated that post, we had a customer running out of disk space in his […]

Why ALTER TABLE runs faster on Percona Server 5.5 vs. MySQL 5.5

Some of us Perconians are at OpenStack summit this week in Atlanta. Matt Griffin, our director of product management, tweeted about the turbo-hipster CI talk about their experience of ALTER TABLEs running faster on Percona Server. Oracle’s Morgan Tocker then tweeted in response, asking why this was the case. I decided that the simplest way to […]

InnoDB Full-text Search in MySQL 5.6: Part 3, Performance

This is part 3 of a 3 part series covering the new InnoDB full-text search features in MySQL 5.6. To catch up on the previous parts, see part 1 or part 2 Some of you may recall a few months ago that I promised a third part in my InnoDB full-text search (FTS) series, in […]

MySQL and the SSB – Part 2 – MyISAM vs InnoDB low concurrency

This blog post is part two in what is now a continuing series on the Star Schema Benchmark. In my previous blog post I compared MySQL 5.5.30 to MySQL 5.6.10, both with default settings using only the InnoDB storage engine.  In my testing I discovered that innodb_old_blocks_time had an effect on performance of the benchmark.  There was […]

InnoDB Full-text Search in MySQL 5.6 (part 1)

I’ve never been a very big fan of MyISAM; I would argue that in most situations, any possible advantages to using MyISAM are far outweighed by the potential disadvantages and the strengths of InnoDB. However, up until MySQL 5.6, MyISAM was the only storage engine with support for full-text search (FTS). And I’ve encountered many […]

ALTER TABLE: Creating Index by Sort and Buffer Pool Size

Today I was looking at the ALTER TABLE performance with fast index creation and without it with different buffer pool sizes. Results are pretty interesting. I used modified Sysbench table for these tests because original table as initially created only has index on column K which initially contains only zeros, which means index is very […]

Using innodb_sys_tables and innodb_sys_indexes

I was playing with Percona Server today and found fast_index_creation does not work quite exactly like described in the manual. The point I’m looking to make though it would be very hard to catch this problem without additional information_schema tables we added in Percona Server. I was doing simple ALTER TABLE such as: “alter table […]

Innodb vs MySQL index counts

I had a customer recently who a few strange errors in their mysqld.err log:

This customer was running Percona Server 5.1 and they got this error on two tables during a maintenance window when they were adding indexes to the same tables.  We had a suspicion that it had something to do with Fast […]