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Search Results for: mysql with limited memory amount

Should we give a MySQL Query Cache a second chance ?

Over last few years I’ve been suggesting more people to disable Query Cache than to enable it. It can cause contention problems as well as stalls and due to coarse invalidation is not as efficient …


Why you should ignore MySQL’s key cache hit ratio

I have not caused a fist fight in a while, so it’s time to take off the gloves. I claim that somewhere around of 99% of advice about tuning MySQL’s key cache hit ratio is …


High-Performance Click Analysis with MySQL

We have a lot of customers who do click analysis, site analytics, search engine marketing, online advertising, user behavior analysis, and many similar types of work.  The first thing these have in common is that …


How Percona does a MySQL Performance Audit

Our customers or prospective customers often ask us how we do a performance audit (it’s our most popular service). I thought I should write a blog post that will both answer their question, so I …


Is disk Everything for MySQL Performance ?

I read very nice post by Matt today and it has many good insights though I can’t say I agree on all points. First there is a lot of people out where which put it …


Evaluating IO subsystem performance for MySQL Needs

I’m often asked how one can evaluate IO subsystem (Hard drive RAID or SAN) performance for MySQL needs so I’ve decided to write some simple steps you can take to get a good feeling about …


MySQL Query Cache

MySQL has a great feature called “Query Cache” which is quite helpful for MySQL Performance optimization tasks but there are number of things you need to know. First let me clarify what MySQL Query Cache …


Thoughts on MySQL Replication

Brian Aker recently published good write up about using MySQL replication. The piece I find missing however is good description of warning about limits of this approach as well as things you need to watch …


MySQL Server Memory Usage

Every so often people ask me the question how should they estimate memory consumption by MySQL Server in given configuration. What is the formula they could use. The reasons to worry about memory usage are …


Bypassing SST in Percona XtraDB Cluster with binary logs

In my previous post, I used incremental backups in Percona XtraBackup as a method for rebuilding a Percona XtraDB Cluster (PXC) node without triggering an actual SST. Practically this reproduces the SST steps, but it …