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Search Results for: XA transaction

Flexviews is a working scalable database transactional memory example

http://Flexvie.ws fully implements a method for creating materialized views for MySQL data sets. The tool is for MySQL, but the methods are database agnostic. A materialized view is an analogue of software transactional memory. You …


How small changes impact complex systems – MySQL example

If you’ve been studying complex systems you know what minor changes might cause consequences of much greater proportions, sometimes causing some effects that are not easily explained at first. I recently ran across a great …


Innodb transaction history often hides dangerous ‘debt’

In many write-intensive workloads Innodb/XtraDB storage engines you may see hidden and dangerous “debt” being accumulated – unpurged transaction “history” which if not kept in check over time will cause serve performance regression or will …


More then 1000 columns – get transactional with TokuDB

Recently I encountered a specific situation in which a customer was forced to stay with the MyISAM engine due to a legacy application using tables with over 1000 columns. Unfortunately InnoDB has a limit at …


Examining 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 …


On TokuMX (and MongoDB) Replication and Transactions

In my last post, I describe the differences between a TokuMX oplog entry and a MongoDB oplog entry. One reason why the entries are so different is that TokuMX supports multi-statement and multi-document transactions. In …


Lock Escalation and Big Transactions in TokuDB and TokuMX

We have seen TokuDB lock escalation stall the execution of SQL operations for tens of seconds. To address this problem, we changed the lock escalation algorithm used by TokuDB and TokuMX so that the cost …


February 6 Webinar: Transactions and MongoDB – Ways To Have It All

MongoDB is loved by developers for its productivity, but productivity can decline when you begin to write enterprise applications and realize that some database features you take for granted are not available in MongoDB. One …


Percona Server: Thread Pool Improvements for Transactional Workloads

In a previous thread pool post, I mentioned that in Percona Server we used an open source implementation of MariaDB’s thread pool, and enhanced/improved it further. Below I would like to describe some of these …


Four Benefits of TokuMX Transactions for MongoDB Applications

From the application’s perspective, TokuMX behaves very similarly, if not identically, to MongoDB in many ways. But in one subtle yet important way, on non-sharded clusters, TokuMX is different. With MongoDB, operations on each single …