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Displaying posts with tag: mysqlquicksand (reset)
Putting Galera SST Compression on the benchmark

I mentioned in my Galera crash (un)safe post that it’s bad if a SST is triggered on a large dataset. On a Galera node an SST will simply wipe the contents of the MySQL data directory and copy a snapshot from another node in the cluster. For consistency this is a favorable thing to do, but from an HA perspective it isn’t: one node in the cluster is unavailable and another one is acting as donor. This means, if you have a three node Galera cluster, only two are available where one has “degraded” performance.

This could have quite high impact, for instance in the proxysql_galera_checker script only synced nodes are selected to receive traffic. By default the donor nodes will not receive any traffic and now the cluster only has one node left to serve traffic. Don’t worry: if there are no synced …

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Hyperconverging and Galera cluster

What is hyperconverging?

Hyperconverging is the latest hype: do things more efficiently with the resources that you have by cramming as many virtual machines on the same hypervisor. In theory this should allow you to mix and match various workloads to make the optimum use of your hypervisor (e.g. all cores used 100% of the time, overbooking your memory up to 200%, moving virtuals around like there is no tomorrow). Any cloud provider is hyperconverging their infrastructure and this has pros and cons. The pro is that it’s much cheaper to run many different workloads while the con clearly is when you encounter noisy neighbors. As Jeremy Cole said: “We are utilizing our virtual machines to the max. If you are on the same hypervisor as us, sorry!”

Apart from cloud providers, you could hyperconverge your infrastructure yourself. There are a few hardware/software vendors out there that will help you with that and at one of my …

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Is Galera trx_commit=2 and sync_binlog=0 evil?

It has been almost 5 years since I posted on my personal MySQL related blog. In the past few years I have worked for Severalnines and blogging both on their corporate blog and here would be confusing. After that I forgot and neglected this blog a bit, but it’s time to revive this blog!

Speaking at Percona Live Europe – Amsterdam 2019

Why? I will be presenting at Percona Live Europe soon and this blog and upcoming content is the more in-depth part of some background stories in my talk on benchmarking: Benchmarking should never be optional. The talk will mainly cover why you should always benchmark your servers, clusters and entire systems.

If you wish to see me present, you can receive 20% discount using this code: CMESPEAK-ART. Now let’s move on to the real …

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Organizing the MySQL UG NL on 22nd of February

It has been a bit of a rollercoaster ride for us since the Percona Live London posting. The team has expanded with two new DBAs, I was invided to give a talk on selected the Percona Live Conference & Expo 2013 in April and at the same time Spil Games is organizing the second MySQL User Group NL meeting on Friday February 22nd of February. I did not realize it is next week and never posted about it, so there it is!

The meeting schedule is as following:
17:00 Spil Games Pub Open
18:00 Introduction
18:15 “MySQL User Defined Functions” by Roland Bouman
19:00 Pizza
20:00 “Total cost of ownership” by Zsolt Fabian (Spil Games)

Before and after the meeting drinks …

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Why MySQL Quicksand?

Why MySQL Quicksand? Well, that’s easy enough: from experience I’ve learned that the margin between a fully functional MySQL database server and one that’s going into a grinding halt can be a very thin hairline. Getting it back to work may be a hell but it will, most of the time, be very possible to save your server.

Quicksand has the same trouble: it may appear to be quite sold, but a very small disturbance can cause a sudden decrease in viscosity and change it from solid to a liquid like substance. You will sink into it but, generally, not drown.

What will be posted here? Well not everything will be exclusively MySQL but mostly be related to it. You can expect warstories, brainstorms, reposts, links, etc.

My main goal is that whatever I post here will be useful for someone else.


Tagged: about, …

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Just started here…

Just started MySQL Quicksand and hopefully it will turn out to be something fruitful.

Why?

Well, I feel the urge to share some experience and willing to learn from the feedback.

What to expect here?

Well I do have a lot of warstories to share and tons of stuff that I try to find out when reading other peoples blogs… More stuff to come soon!


Tagged: mysql

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Showing entries 1 to 6