This small article is about nicely depicting memory usage prior to OOM killers show.

I have started MySQL with:

/home/shahriyar.rzaev/XB_TEST/server_dir/PS131117-percona-server-5.7.19-17-linux-x86_64/bin/mysqld --no-defaults \
--innodb_buffer_pool_size=1G --innodb_log_file_size=1G --innodb_page_size=64K --early-plugin-load=keyring_file.so \ --keyring_file_data=/home/shahriyar.rzaev/XB_TEST/server_dir/PS131117-percona-server-5.7.19-17-linux-x86_64/mysql-keyring/keyring \
--log-bin=mysql-bin --log-slave-updates --server-id=1 --gtid-mode=ON --enforce-gtid-consistency --binlog-format=row --core-file --basedir=/home/shahriyar.rzaev/XB_TEST/server_dir/PS131117-percona-server-5.7.19-17-linux-x86_64 \
--tmpdir=/home/shahriyar.rzaev/XB_TEST/server_dir/PS131117-percona-server-5.7.19-17-linux-x86_64/data \
--datadir=/home/shahriyar.rzaev/XB_TEST/server_dir/PS131117-percona-server-5.7.19-17-linux-x86_64/data \
--plugin-load-add=tokudb=ha_tokudb.so …

Hi,
In this post I am going to show some tricks on using BATS framework + PyTest + Python X Plugin things, to have combined, simple test solutions.

Let’s describe MySQL X Plugin side, here is the full class:

# Connecting to MySQL and working with a Session
import mysqlx

class MyXPlugin:

    def __init__(self, schema_name, collection_name):
        # Connect to a dedicated MySQL server
        self.session = mysqlx.get_session({
            'host': 'localhost',
            'port': 33060,
            'user': 'bakux',
            'password': 'Baku12345',
            'ssl-mode': mysqlx.SSLMode.DISABLED
        })

        self.schema_name = schema_name
        self.collection_name = collection_name

        # Getting schema object
        self.schema = self.session.get_schema(self.schema_name)
        # Creating collection
        self.schema.create_collection(self.collection_name, reuse=True)
        # Getting collection object …

This post is about, how I have tried to make simple Python script using mysqlx module work with MyRocks.
This is also related to pytest, as I have implemented simple pytest tests to call them from bash file.

So let’s discuss problem description:
The base problem is, by default when you create collection using Python X Plugin, the collection will have, 1 json type column called `doc` and 1 generated column from this `doc` column called `_id`.
So basically, you can not alter table engine to MyRocks because it will give an error something like:

ERROR 3106 (HY000): 'Specified storage engine' is not supported for generated columns.

The result:

Well, it can be solved by dropping generated `_id` column. Here we are encountering another issue that, if you have table with json data, please do NOT alter it to MyRocks, otherwise, you will get some weird results as described here:

…

This post is about simple usage of mysqlx module i.e X Plugin with latest Connector/Python DMR.
The version of Python Connector is 8.0.4.

Installing:

wget https://dev.mysql.com/get/Downloads/Connector-Python/mysql-connector-python-8.0.4-0.1.dmr.el7.x86_64.rpm
sudo yum install mysql-connector-python-8.0.4-0.1.dmr.el7.x86_64.rpm

Sample Python code:

# Connecting to MySQL and working with a Session
import mysqlx

# Connect to a dedicated MySQL server
session = mysqlx.get_session({
    'host': 'localhost',
    'port': 33060,
    'user': 'bakux',
    'password': 'Baku12345',
    'ssl-mode': mysqlx.SSLMode.DISABLED
})

schema = session.get_schema('generated_columns_test')

# Create 'my_collection' in schema
schema.create_collection('my_collection')

# Get 'my_collection' from schema
collection = schema.get_collection('my_collection')

assert(True == collection.exists_in_database())

# You can also add multiple documents at once …

I would like to inform community, as an Azerbaijan MySQL User Group leader I have attanded to E-Days-2016 and talked about MySQL, Open Source and the power of “BUG”s
Here are some photos from meetup:

Azerbaijan MySQL User Group next meeting was with IT girls from “WoWoman” division in Baku.
We have talked about Linux and MySQL.
There was a hands-on lab about installing Ubuntu, working with basic Linux commands.

I would like to share some photos from this event

Today i want to share experience with latest Percona Server where TokuDB and TokuBakcup plugins have been added in main source.
So there is no other steps needed here to get and started.
But in recent discussion in our local community, there was a question: “How about installing MySQL on CentOS minimal”.
The reason was clear, because somebody got too many errors in fresh CentOS 7 minimal.

I want to share here full steps.
Please follow numbers:

1. Getting Source package:

[root@testing-host1 ~]# wget https://www.percona.com/downloads/Percona-Server-5.6/Percona-Server-5.6.27-75.0/source/tarball/percona-server-5.6.27-75.0.tar.gz

Unpacking:
tar -xvf percona-server-5.6.27-75.0.tar.gz

2. Compiling using CMAKE:

If you have read the documentation:

…

Today’s topic is about how to test Group Replication plugin in easy way, with using MySQL Sandbox
But firstly we must compile MySQL with Group Replication plugin, refer to previous topic -> Compiling Group Replication Plugin

Who did not use Sandbox before, please refer to official link and read a bit more. It is wonderful tool for installing, testing new things with MySQL. Especially if you have new MySQL release to test and want to install 3 or 5 instances, just use MySQL Sandbox and it will do this work for you.

In our condition, we have already compiled MySQL with our plugin. So we have source folder in -> /home/sh/Sandboxes/mysql-group-replication-0.5.0-dmr/BIN

…

Recently, we have discussed BUGs with our local community members. Where the half off people said that, they have seen “Assertion Failure” errors in error log. And the question was what is this at all?

In general “assert” is a code portion put by developer to handle certain things.

Well, i am not a core MySQL developer and my C/C++ knowledge is limited to simple calculator But i will try to explain where all these “Assertion Failure” errors come up.
The exact reason of failing Assertion/crash should be known by core developers. I know how to crash, they know how to fix. You help developers to reproduce a crash filling a bug report, by uploading test cases or maybe the core dump, backtrace etc.
Say, for eg, if you try to create a view after getting “full disk” error you will crash MySQL. See related BUG report -> …

Today’s topic is related primarily to compiling MySQL from source using CMAKE and what kind of issues we encounter during this task. We want to install MySQL 5.6.19 with Debug+Valgrind etc. On CentOS 7 here are my dependency packages start point:

[root@centos-base ~]# yum install zlib zlib-devel openssl openssl-devel valgrind valgrind-devel cmake gcc cpp ncurses ncurses-devel

Here is my CMAKE command:

[root@centos-base mysql-5.6.19]# cmake -DCMAKE_INSTALL_PREFIX=/opt/mysql-5.6.19 -DMYSQL_DATADIR=/var/lib/mysql -DSYSCONFDIR=/opt/mysql-5.6.19 -DWITH_SSL=system -DMYSQL_TCP_PORT=3306 -DMYSQL_UNIX_ADDR=/opt/mysql-5.6.19/mysqld.sock -DDEFAULT_CHARSET=utf8 -DDEFAULT_COLLATION=utf8_general_ci -DWITH_DEBUG=1 -DCOMPILATION_COMMENT="Shahriyar Rzayev's CentOS MySQL-5.6.19" -DOPTIMIZER_TRACE=1 -DWITH_ZLIB=system -DWITH_VALGRIND=1 -DCMAKE_C_FLAGS=-DHAVE_purify -DCMAKE_CXX_FLAGS=-DHAVE_purify

If you try to run …