Monthly Archives - July 2015

MySQL QA Episode 10: Reproducing and Simplifying: How to get it Right

MySQL QA Episode 10

Welcome to the 10th episode in the MySQL QA series! Today we’ll talk about reproducing and simplifying: How to get it Right.
Note that unless you are a QA engineer stuck on a remote, and additionally difficult-to-reproduce or difficult-to-reduce bug, this episode will largely be non-interesting for you.
However, what you may like to see – […]

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Why base64-output=DECODE-ROWS does not print row events in MySQL binary logs

MySQL binary logs

Lately, I saw many cases when users specified the option
–base64-output=DECODE-ROWS  to print out a statement representation of row events in MySQL binary logs just to get nothing. Reason for this is obvious: option
–base64-output=DECODE-ROWS  does not convert row events into its string representation, this is the job of the option
— verbose. But […]

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Multi-source replication in MySQL 5.7 vs Tungsten Replicator

MySQL 5.7 comes with a new set of features and multi-source replication is one of them. In few words this means that one slave can replicate from different masters simultaneously.
During the last couple of months I’ve been playing a lot with this trying to analyze its potential in a real case that I’ve been […]

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MySQL QA Episode 9: Reducing Testcases for Experts: multi-threaded reducer.sh

Welcome to MySQL QA Episode 9. This episode will go more in-depth into reducer.sh: Reducing Testcases for Experts: multi-threaded reducer.sh
We will explore how to use reducer.sh to do true multi-threaded testcase reduction – a world’s first.
Topics:

Expert configurable variables & their default reducer.sh settings

PQUERY_MULTI
PQUERY_MULTI_THREADS
PQUERY_MULTI_CLIENT_THREADS
PQUERY_MULTI_QUERIES
PQUERY_REVERSE_NOSHUFFLE_OPT

Full-screen viewing @ 720p resolution recommended.

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InnoDB vs TokuDB in LinkBench benchmark

Previously I tested Tokutek’s Fractal Trees (TokuMX & TokuMXse) as MongoDB storage engines – today let’s look into the MySQL area.
I am going to use modified LinkBench in a heavy IO-load.
I compared InnoDB without compression, InnoDB with 8k compression, TokuDB with quicklz compression.
Uncompressed datasize is 115GiB, and cachesize is 12GiB for InnoDB and 8GiB […]

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