… to get to disk. This has no effect on standard MySQL replication from this instance, since MySQL replication is asynchronous. What about semi-sync MySQL… relax synchronous replication. You can’t change the law, you can only adapt around it, but how might you do that ? Write to… law is going to cause you trouble and you are not prepared to adapt to work with it, PXC/Galera Synchronous replication is probably…
Post: Galera Flow Control in Percona XtraDB Cluster for MySQL
May 2, 2013 By 5 Comments
…: how would synchronous replication get behind? As I’ve mentioned before, Galera’s replication is synchronous to the point of ensuring transactions are copied to… to allow replication to resume as soon as possible. An example configuration tuning flow control in a master/slave cluster might be: mysql…
Post: Testing the Micron P320h
April 16, 2013 By 7 Comments
…, these numbers equate to over 110,000 write IOPS and almost 205,000 read IOPS. When we switch over to synchronous IO, we find that the card is quite capable of matching the asynchronous performance: Synchronous read reaches peak… have maximum throughput with latency just over 3ms. How well does it perform with MySQL? Exact results vary, depending upon the usual…
Post: Percona Live MySQL Conference and Expo 2013: The talks I want to see
February 12, 2013 By 4 Comments
… for anyone starting to explore how to get beyond a single-mastered data store and why it’s a hard problem to solve. State of the Art for MySQL… decision points he tends to bring to the table with this kind of architecture. Case Study: Designing a synchronous multi-master cluster for…
Post: How Does Semisynchronous MySQL Replication Work?
January 19, 2012 By 24 Comments
… being asked about MySQL‘s semi-synchronous replication. I find that there are often a number of misconceptions about how semi-synchronous replication really… also committed successfully. In MySQL‘s semi-synchronous replication, the commit completes before the transaction is even sent to any of the replicas… out of the bag and there’s no way to force replicas to do anything. As a result, the effect is that…
Post: Percona XtraDB Cluster - installation and setup webinar follow up Q&A
October 28, 2012 By 4 Comments
…, galera and built-in mysql replication are independent from each …synchronizing with the group, are the other two nodes available to serve data during the synchronization? A: The node synchronizing…how to start up a cluster from scratch (i.e. a standalone XtraDB Cluster machine, convert it to…
Post: Automation: A case for synchronous replication
September 19, 2012 By 2 Comments
… lets see how Synchronous Replication solutions such a Percona XtraDB Cluster and MySQL Cluster are different. Synchronous replication essentially allows you to work with database… to operational state. Conclusion: If you’re looking for setting up HA solution for MySQL check out synchronous replication based solutions in additionally to MySQL…
Post: Understanding Multi-node writing conflict metrics in Percona XtraDB Cluster and Galera
November 20, 2012 By 17 Comments
…-phase commit to replicate (where all nodes commit synchronously with the client), but it is instead something Codership calls “virtually synchronous” replication. This… synchronous“? Because simply getting our writesets to every node on commit means that they are guaranteed to apply — therefore we don’t have to… can’t think of how to reliably produce local certification errors without just a lot of fast modifications to a single row, because…
Post: MongoDB Approach to database synchronization
April 30, 2010 By 5 Comments
… chance to write more about it. This post is about one replication problem and how MongoDB solves it. If you’re using MySQL… for failed master to scan its log files to find all object ids which were modified from the point slave synchronized successfully and… the Master after failover to Slave happened and they can be dumped to local file (in case one wants to synchronize them manually) and…
Post: Product to try: MySQL/MariaDB-Galera 0.8
June 13, 2011 By 34 Comments
… quite easy to add support for Percona XtraBackup to propagate nodes. Why MySQL/MariaDB + Galera 0.8 is interesting? It allows to solve following… is possible to use it in traditional master-slave setups, but with big difference – with Galera we have Semi-synchronous slaves. How it works on slaves: slaves just acknowledge reception of a network packet (not a transaction). Transaction is not guaranteed to…
