Tag - kernel

Tune Linux Kernel Parameters For PostgreSQL Optimization

linux kernel parameters

For optimum performance, a PostgreSQL database depends on the operating system parameters being defined correctly. Poorly configured OS kernel parameters can cause degradation in database server performance. Therefore, it is imperative that these parameters are configured according to the database server and its workload. In this post, we will discuss some important Linux kernel […]

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20-30% Performance Hit from the Spectre Bug Fix on Ubuntu

Spectre Bug Fix on Ubuntu

In this blog post, we’ll look at the performance hit from the Spectre bug fix on Ubuntu.
Recently we measured the performance penalty from the Meltdown fix on Ubuntu servers. It turned out to be negligible.
Today, Ubuntu made a Spectre bug fix on Ubuntu available, shipped in kernel 4.4.0-112. As with the Meltdown fix, we […]

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Meltdown and Spectre: CPU Security Vulnerabilities

CPU Security Vulnerabilities

In this blog post, we examine the recent revelations about CPU security vulnerabilities.
The beginning of the new year also brings to light fresh and new CPU security vulnerabilities. Today’s big offenders originate on the hardware side – more specifically, the CPU. The reported hardware kernel bugs allow for direct access to data held in the […]

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OOM relation to vm.swappiness=0 in new kernel

I have recently been involved in diagnosing the reasons behind OOM invocation that would kill the MySQL server process. Of course these servers were primarily running MySQL. As such the MySQL server process was the one with the largest amount of memory allocated.
But the strange thing was that in all the cases, there was […]

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