Tag: performance

Working with consulting clients is rewarding, interesting, and challenging. In discussion with some of my colleagues, I’ve noticed the same performance challenges come up over and over again across clients with completely different hardware, industry verticals, levels of staff seniority,…

Database unavailability or outright failure is no joke. Not only do such incidents often cause massive internal stress (along with the inevitable blame game between IT staff), but they can also negatively impact business outcomes and lead to dissatisfied or…

In this post, I’ll present the statspack_top_sqls.sql script, which returns SQL performance statistics by mining the Statspack repository. In a previous blog post, I presented the statspack_load_trends.sql and the AWR_load_trends.sql scripts, which provide a high-level overview of workload dynamics on…

There are various ways that we can approach the analysis of a past database performance problem. The initial steps usually differ based on their scope. Is it limited to a certain SQL/process/task, or is it perceived as a database-wide slowdown?…

Short summary: Queries to ALL_SYNONYMS cause FTS of SYS.OBJ$ which can’t be avoided.

Introduction Every new version of SQL Server ships with exciting new features. One of the simplest but important features is Automatic Tuning. Before covering this new feature, let’s analyze the old ways so we can understand what is really automated…

For the Oracle Code series of events I have delivered an older but still relevant talk called “Tackling Time Troubles.” Half of it is nice-to-know geek trivia and the other half is a few points on how to avoid very…

Having good historial metrics monitoring in place is critical for properly operating, maintaining and troubleshooting database systems, and Percona Monitoring and Management is one of the options we recommend to our clients for this. One common concern among potential users…

If you’ve ever had to evaluate server performance, you likely know of sysbench, a performance benchmark project started by Peter Zaitsev with continued development by Alexey Kopitov. The last official release was the version 0.4, which is found in almost…

It’s well known that mmap helps to improve performance in particular use-cases (especially if your working set fits an available memory). This doesn’t mean that the file itself has to fit memory. mmaps provides real benefits over the other IO…