Tag - Hardware

Posts have something to do with hardware issues

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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Using NVMe Command Line Tools to Check NVMe Flash Health

NVMe Flash Health

In this blog post, I’ll look at the types of NVMe flash health information you can get from using the NVMe command line tools.
Checking SATA-based drive health is easy. Whether it’s an SSD or older spinning drive, you can use the
smartctl command to get a wealth of information about the device’s performance and health. […]

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How to improve InnoDB performance by 55% for write-bound loads

Update: do not do this, this has been proven to corrupt data!
 
During April’s Percona Live MySQL Conference and Expo 2014, I attended a talk on MySQL 5.7 performance an scalability given by Dimitri Kravtchuk, the Oracle MySQL benchmark specialist. He mentioned at some point that the InnoDB double write buffer was a real performance […]

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Beware: ext3 and sync-binlog do not play well together

One of our customers reported strange problem with MySQL having extremely poor performance when sync-binlog=1 is enabled, even though the system with RAID and BBU were expected to have much better performance.
The problem could be repeated with SysBench as follows:

Shell

./sysbench –num-threads=2 –test=oltp –oltp-test-mode=complex –oltp-table-size=100000 –oltp-distinct-ranges=0 –oltp-order-ranges=0 –oltp-sum-ranges=0 –oltp-simple-ranges=0 –oltp-point-selects=0 –oltp-range-size=0 –mysql-table-engine=innodb […]

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