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Search Results for: causes of table fragmentation

Avoiding Fragmentation with Fractal Trees

Summary B-trees suffer from fragmentation. Fragmentation causes headaches — in query performance and space used. Solutions, like dump and reload or OPTIMIZE TABLE are a pain and not always effective. Fractal trees don’t fragment. So …


Attempting to Quantify Fragmentation Effects

We often hear from customers and MySQL experts that fragmentation causes problems such as wasting disk space, increasing backup times, and degrading performance. Typical remedies include periodic “optimize table” or dump and re-load (for example, …


MySQL File System Fragmentation Benchmarks

Few days ago I wrote about testing writing to many files and seeing how this affects sequential read performance. I was very interested to see how it shows itself with real tables so I’ve got …


Illustrating Primary Key models in InnoDB and their impact on disk usage

On a recent engagement I worked with a customer who makes extensive use of UUID() values for their Primary Key and stores it as char(36), and their row count on this example table has grown to …


Use TokuMX Partitioned Collections in Place of TTL Indexes

Take the following scenario. You have a time-series data application for which you would like to store a rolling period of data. For example, you may want to maintain the last six months of traffic …


Memory allocators: MySQL performance improvements in Percona Server 5.5.30-30.2

In addition to the problem with trx_list scan we discussed in Friday’s post, there is another issue in InnoDB transaction processing that notably affects MySQL performance – for every transaction InnoDB creates a read view …