Finding and removing unused indexes is a pretty common technique to improve overall performance of relational databases. Less indexes means faster insert and updates but also less disk space used. The usual way to do it is to log all queries’ execution plans and then get a list of those indexes that are not used. Same theory applies to MongoDB and TokuMX so in this blog post I’m going to explain how to find those.
State Snapshot Transfer (SST) at a glancePXC uses a protocol called State Snapshot Transfer to provision a node joining an existing cluster with all the data it needs to synchronize. This is analogous to cloning a slave in asynchronous replication: you take a full backup of one node and copy it to the new one, while tracking the replication position of the backup.
I was reading Fred Wilson’s comments recently on The Bitcoin XT Fork. In it he discussed how open source developers manage their projects. A group of open source core developers are a democratic system. I was surprised by this comment because I had never thought if it as democratic. Here are my thoughts… Join 28,000 […]
I have heard this question quite often: “At busy times, our replicas start lagging quite frequently. We are using N schemas, so which performance boost could we expect from MySQL 5.6 parallel replication?” Here is a quick way to give you a rough estimate of the potential benefit.General ideaIn MySQL 5.6, parallelism is added at the schema level. So in theory, if you have N schemas and if you use N parallel threads, replication could be up to N times faster. This assumes at least 2 things:
In the past years, both MySQL 5.6, MySQL 5.7 and MariaDB 10 have been successful implementing new features. For many DBAs, the “old way” of replicating data is comfortable so taking the action to implement these new features seems like a momentous leap rather then a simple step. But perhaps it isn’t that complicated…
In MySQL QA Episode #12, “MySQL is Crashing, now what?,” Roel demonstrated how to collect crash-related information that will help Percona discover what the issue is that you are experiencing, and fix it.