My previous poll got a great response so I thought I should continue these series.
The question of the day today is How much data do your store in your largest MySQL instance ? I’m interested about single instance not the total amount of data you have in MySQL in your Sharded replicated environment. Feel free to share details in comments – are you using MyISAM or Innodb ? Is it working out well for you or are there any challenges you’re seeing ?

Note: There is a poll embedded within this post, please visit the site to participate in this post's poll.

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We have a backup server that, from time to time, gets errors when doing mysqldump backups (we do physical backups and logical backups, but the physical backups work fine). The errors look like this:
mysqldump: Couldn't execute 'SHOW FUNCTION STATUS WHERE Db = 'mozillians_org'': Out of resources when opening file '/tmp/#sql_3b63_0.MYI' (Errcode: 24) (23)
mysqldump: Error: 'Out of resources when opening file '/tmp/#sql_3b63_2.MYI' (Errcode: 24)' when trying to dump tablespaces
I tried restarting MySQL, and that helped, for a while. It helped to the point that we put in a cron job to restart MySQL every 4 hours so we would not run out of resources.
But that did not last forever. We tried restarting more frequently. We tried increasing ulimits. Again, this helped for a while, or seemed to.
When it happened again today, I decided to look around again for what other folks’ experience was. I ended up finding …

We have a backup server that, from time to time, gets errors when doing mysqldump backups (we do physical backups and logical backups, but the physical backups work fine). The errors look like this:
mysqldump: Couldn't execute 'SHOW FUNCTION STATUS WHERE Db = 'mozillians_org'': Out of resources when opening file '/tmp/#sql_3b63_0.MYI' (Errcode: 24) (23)
mysqldump: Error: 'Out of resources when opening file '/tmp/#sql_3b63_2.MYI' (Errcode: 24)' when trying to dump tablespaces
I tried restarting MySQL, and that helped, for a while. It helped to the point that we put in a cron job to restart MySQL every 4 hours so we would not run out of resources.
But that did not last forever. We tried restarting more frequently. We tried increasing ulimits. Again, this helped for a while, or seemed to.
When it happened again today, I decided to look around again for what other folks’ experience was. I ended up finding …

"Kris, please have a look at our database. We are running a materialized dataset processor, and on a database with about 40 GB of buffer pool and a database size of 6 GB, we are observing swapping."

Now, that is interesting. The box in question has 48 GB of memory, and indeed, hardly 6 GB of data.

CODE: mysql> select 
 -> sum(data_length+index_length)/1024/1024/1024 as gb 
 -> from tables 
 -> where table_schema not in ('information_schema', 'performance_schema', 'mysql');
+----------------+
| gb             |
+----------------+
| 5.832778930664 |
+----------------+
1 row in set (0.00 sec)
Yet, at the same time in "top", and growing:
CODE: …

I've said it before and I'll say it again: Software patents are evil. They allow the work of innovators to be ambushed and raise the cost of technology innovation. But finding a viable solution to the software patent mess isn't easy.

read more

Mark, the background commit (every 5 sec) kicks in only if there are uncommitted transactions with some "daemon_memcached_w_batch_size" value, and number of transactions not yet cross the batch size. By default daemon_memcached_w_batch_size is 1, which is the same as auto-commit. And the background commit will not do any commits (since all are committed). But you have a valid point that the test harness needs to make sure the commit batch size in both case.

I recently had a need to import a bunch of data into MySQL, and for reasons I won’t get into here, LOAD DATA INFILE wasn’t working for me.  I was in a hurry to get the data into MySQL so that I could filter it, and didn’t have time to work through my LOAD DATA INFILE issues.  Looking around for another way to quickly get my tab-delimited data into MySQL quickly, I decided to use the MySQL for Excel plugin.  If you haven’t seen this yet, and you have Excel, it might be worth your while.

In my case, I was able to quickly copy and paste the tab-delimited text file into an Excel spreadsheet, connect MySQL for Excel to the MySQL database and append the data to the existing table.  You’ll need to have Excel, MySQL and the MySQL for Excel plugin.  The latter two can be installed from a single download using the …

In case you missed this......  

MySQL Server 5.6.8 RC was announced today.

MySQL Server 5.6.8 (Release Candidate) is a new version of the world's most popular open source database. 

Please download and test it out. Oracle is eager for any feedback that you might have on this release. 

This is not necessarily going to be a comprehensive post, but I learned somethings about MySQL SSL today that I thought would be worth sharing.

I was setting up a PRM install for a customer and one of the requirements was SSL replication.  In this particular case, I had setup PRM first, and then was working to get the other requirements configured.  I knew from experience that it was best to ensure SSL was working properly from the command line first before trying to get replication to use it via PRM’s automation that does the CHANGE MASTER for you.  Eliminate the variables.

The customer provided me with the CA cert, the private key, and the …

It has been a little while since I have had the time to sit and write again and I can admit that I quite miss it. From a community standpoint, myself and the intern team have been really busy with getting the new websites in place. We also have alot plans for some really awesome projects being planned with some other open source companies like Akiban, as well as some Social Media contests. Recently though, I have been handling a fair amount of requests dealing with common issues, ranging from simple connections to permission issues. As a general rule, approaching these issues, there is a common few steps that are taken to help eliminate where the issue lies.

On Unix/Linux:

1. From prompt type 'sudo su'
2. Enter your password if prompted
3. type /etc/init.d/mysqld-ib start
4. If a process is already running, it will let you know
5. type mysql-ib -u{username}
6. Once the mysql prompt …