Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

In case you missed last week’s column, don’t forget to read the fairly lengthy FOSDEM MySQL & Friends DevRoom summary.

From a Percona Live Santa Clara 2018 standpoint, beyond the tutorials getting picked and scheduled, the talks have also been picked and scheduled (so you were very likely getting acceptance emails from the Hubb.me system by Tuesday). The rejections have not gone out yet but will follow soon. I expect the schedule to go live either today (end of week) or early next week. Cheapest tickets end March 4, so …

Join Percona Chief Evangelist Colin Charles as he covers happenings, gives pointers and provides musings on the open source database community.

Still on Meltdown/Spectre, this time MariaDB Corporation has published Meltdown Vulnerability Impact On MariaDB Server – interesting the comparison between glibc/tcmalloc. Worthy Facebook thread about this too, with a bit of chat about MongoDB performance. Officially MongoDB says a degradation of 10-15%. ScaleGrid has a good post, in which they test MongoDB against …

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 measured the effect of this update. Unfortunately, we observed a major performance penalty on MySQL workloads with this new kernel.

Our benchmark used the following:

System:

• CPU:
  • 2 x Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz (Codename Haswell)
  • /proc/cpuinfo has 48 …

In this blog post, we’ll look at does the Meltdown fix affect performance for MySQL on bare metal servers.

Since the news about the Meltdown bug, there were a lot of reports on the performance hit from proposed fixes. We have looked at how the fix affects MySQL (Percona Server for MySQL) under a sysbench workload.

In this case, we used bare metal boxes with the following specifications:

• Two-socket Intel(R) Xeon(R) CPU E5-2683 v3 @ 2.00GHz (in total 56 entries in /proc/cpuinfo)
• Ubuntu 16.04
• Memory: 256GB
• Storage: Samsung SM863 1.9TB SATA SSD
• Percona Server for MySQL 5.7.20
• Kernel (vulnerable) 4.13.0-21
• Kernel (with Meltdown fix) 4.13.0-25

Please note, the current kernel for Ubuntu 16.04 contains only a Meltdown fix, …

Update: I included the results for when PCID is disabled, for comparison, as a worse case scenario.

After learning about Meltdown and Spectre, I waited patiently to get a fix from my OS vendor. However, there were several reports of performance impact due to the kernel mitigation- for example on the PostgresQL developers mailing list there was reports of up to 23% throughput loss; Red Hat engineers report a regression range of 1-20%, but setting OLTP systems as the worse type of workload. As it will be highly dependent on the hardware and workload, I decided of doing some test myself for the …

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 computer/server’s memory, which in turn might leak sensitive data. Some of the most popular CPUs affected by these bugs are Intel, AMD and ARM.

The most important thing to know is that this vulnerability is not exploitable remotely, and requires that someone execute the malicious code locally. However, take extra precaution when running in virtualized environments (see below for more information).

A full overview (including a technical, in-depth …