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Displaying posts with tag: mysqld_multi (reset)
Fun with Bugs #43 - Bugs Fixed in MySQL 5.7.13

For some reason I do not see numerous public announcements about recent MySQL 5.7.13 release, even though it happened a couple of days ago formally. Maybe that's because we do not have any really "big" new features in this release (new ->> operator for introduced though for those who, unlike me, care about JSON). Still there are many fixes for bugs previously reported by Community (or Oracle engineers, but still in public bugs database), and I'd like to discuss some of them.

Let me start with the bug that was NOT fixed though, Bug #81093, "mysqld_multi not included in mysql-community-server package", reported by Georgi Iovchev and …

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Percona XtraDB Cluster: How to run a 2-node cluster on a single server

I reckon there’s little sense in running 2 or more Percona XtraDB Cluster (PXC) nodes in a single physical server other than for educational and testing purposes – but doing so is still useful in those cases. The most popular way of achieving this seems to be with server virtualization, such as making use of Vagrant boxes. But in the same way you can have multiple instances of MySQL running in parallel on the OS level in the form of concurrent mysqld processes, so too can you have multiple Percona XtraDB Cluster nodes. And the way to achieve this is precisely the same: using dedicated datadirs and different ports for each node.

 

Which ports?4 tcp ports are used by Pecona …

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mysqld_multi: How to run multiple instances of MySQL

The need to have multiple instances of MySQL (the well-known mysqld process) running in the same server concurrently in a transparent way, instead of having them executed in separate containers/virtual machines, is not very common. Yet from time to time the Percona Support team receives a request from a customer to assist in the configuration of such an environment. MySQL provides a tool to facilitate the execution of multiple instances called mysqld_multi:

“mysqld_multi is designed to manage several mysqld processes that listen for connections on different Unix socket files and TCP/IP ports. It can start or stop servers, or report their current status.”

For tests and development purposes, …

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mysqld_multi: How to run multiple instances of MySQL

The need to have multiple instances of MySQL (the well-known mysqld process) running in the same server concurrently in a transparent way, instead of having them executed in separate containers/virtual machines, is not very common. Yet from time to time the Percona Support team receives a request from a customer to assist in the configuration of such an environment. MySQL provides a tool to facilitate the execution of multiple instances called mysqld_multi:

“mysqld_multi is designed to manage several mysqld processes that listen for connections on different Unix socket files and TCP/IP ports. It can start or stop servers, or report their current status.”

For tests and development purposes, …

[Read more]
Fixing MySQL with a comment in the config file

A customer called with an emergency issue: A server that normally runs many MySQL instances wouldn’t start them up. Not only would it not start all of them, it wouldn’t even start the first one. The multiple instances were started through the mysql_multi init script. Perhaps you already know what was wrong!

It turns out that this server’s /etc/init.d/mysql_multi wouldn’t start unless it found the text “mysqld_multi” in the /etc/my.cnf file. Not a [mysqld_multi] config file section, but the text string “mysqld_multi”. It was using this text as a proxy for “I found a [mysqld_multi] configuration section.” This was a rather brittle test, as you can imagine.

After reading the source, I determined that the my.cnf file was fine and the configuration should not be changed, and I could not understand what had changed since it was previously working. Perhaps an automated upgrade or a similar change to the system had …

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Perl is probably a fine scripting language, but on Windows...

Please do not assume Perl is always installed on all platforms. In particular not on Windows! Just as it is probably a bad idea to assume that Windows DOS commands work on Linux! Come on now!

Why am I making a fuzz you ask, do I have a problem with you writing stuff in Perl (personally, I don't even like Perl, but that's another issue)? Nope. But somewhat modern software really should not assume that you have Perl, or DOS, or some other arcane, not terribly standardized piece of software around for a server to do it's job. And MySQL still have a way to go to be reasonably good on Windows. Downloading the lastest RC, 5.5.7, MySQLhas managed to screw up at least two things, at least, in my mind. But maybe that's just me:

  • The optimzied. non debug libraries, are now in /lib under the distribution, not in /lib/opt where they used to be. I see no good reason for this, to be honest (place the libraries where you …
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Showing entries 1 to 6