The Problem HELP, HELP! My Percona XtraDB Cluster version: 5.7.31-31. Single Node is stuck in a joined state. I recently had the privilege to help a client with a fascinating issue. NODE-B dropped out of the 3 node PXC cluster. It looked to be DISK IO that caused NODE-B to fall far behind and eventually […]
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This is the english version of a 2007 article. In de.comp.os.unix.linux.misc somebody asked: Are commands in a script executed strictly sequentially, that is, will the next command only be executed when the previous command has completed, or will the shell automatically start the next command if the system has spare capacity? Can I change the […]
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So this happened: CentOS Project shifts focus to CentOS Stream The future of the CentOS Project is CentOS Stream, and over the next year we’ll be shifting focus from CentOS Linux, the rebuild of Red Hat Enterprise Linux (RHEL), to CentOS Stream, which tracks just ahead of a current RHEL release. CentOS Linux 8, as […]
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Overview In this article, I look at how poorly designed sharding systems and replication systems in PostgreSQL affect query performance in high volume situations, and how to ensure data consistency across many servers. I also discuss how excessive vacuuming generates I/O traffic, and how connection pooling is used to improve transaction throughput by caching connections […]
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The tables in PERFORMANCE_SCHEMA (P_S) are not actually tables. You should not think of them as tables, even if your SQL works on them. You should not JOIN them, and you should not GROUP or ORDER BY them. Unlocked memory buffers without indexes The stuff in P_S has been created with “keep the impact on […]
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At work, I am in an ongoing discussion with a number of people on the Observability of Outliers. It started with the age-old question “How do I find slow queries in my application?” aka “What would I want from tooling to get that data and where should that tooling sit?” As a developer, I just […]
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