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Search Results for: how much memory

Using CHAR keys for joins, how much is the overhead ?

I prefer to use Integers for joins whenever possible and today I worked with client which used character keys, in my opinion without a big need. I told them this is suboptimal but was challenged …

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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 …

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MySQL performance on EC2/EBS versus RDS

A while ago I started a series of posts showing benchmark results on Amazon EC2 servers with RAID’ed EBS volumes and MySQL, versus RDS machines. For reasons that won’t add anything to this discussion, I …

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MySQL for Hosting Providers – how do they manage ?

Working with number of hosting providers I always wonder how do they manage to keep things up given MySQL gives you so little ways to really restrict how much resources single user can consume. I …

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The tool I’ve been waiting for years

I’ve just been pointed to the nice tool which I was waiting for years to see. It is fincore – little perl script which allows you to see what pages of file are cached in …

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10+ Ways to Crash or Overload MySQL

People are sometimes contacting me and asking about bugs like this which provide a trivial way to crash MySQL to the user with basic privileges and asking me what to do. My answer to them …

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Choosing innodb_buffer_pool_size

My last post about Innodb Performance Optimization got a lot of comments choosing proper innodb_buffer_pool_size and indeed I oversimplified things a bit too much, so let me write a bit better description. Innodb Buffer Pool …

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How simple answer are you looking for ?

I’ve got an interesting comment the other day saying “I’ve heard Jay Pipes saying indexes with cardinality lower than 30% are worthless, true?” That is interesting question and it has different answers depending on who …

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What to tune in MySQL Server after installation

My favorite question during Interview for people to work as MySQL DBAs or be involved with MySQL Performance in some way is to ask them what should be tuned in MySQL Server straight after installation, …

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MySQL is crashing: a support engineer’s point of view

In MySQL QA Episode #12, “MySQL is Crashing, now what?,” Roel demonstrated how to collect crash-related information that will help Percona discover what the issue is that you are experiencing, and fix it. As a Support …

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