Properties: 

Applicable To	InnoDB
Server Startup Option	--innodb_log_file_size=<value>
Scope	Global
Dynamic	Yes
Possible Values	Integer: Range: 1M - 4G <1M will be adjusted to 1M
Default Value	5M

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I have a small EC2 instance running with a 25GB EBS volume attached. It has a database on it that I need to manipulate by doing things like dropping indexes and creating new ones. This is on rather large (multi-GB, millions of rows) tables. After running one DROP INDEX operation that ran all day without finishing, I killed it and tried to see what was going on. Here’s the results of the first 10 minutes of testing:

-bash-3.2# dd if=/dev/zero of=/vol/128.txt bs=128k count=1000
1000+0 records in
1000+0 records out
131072000 bytes (131 MB) copied, 0.818328 seconds, 160 MB/s

This looks great. I’d love to get 160MB/s all the time. But wait! There’s more!

-bash-3.2# dd if=/dev/zero of=/vol/128.txt bs=128k count=100000
dd: writing `/vol/128.txt': No space left on device
86729+0 records in
86728+0 records out
11367641088 bytes (11 GB) copied,

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Code and details are here.

Use it for performance debugging rather rather than for performance. It may not make the server run faster, but it can show you where there are problems in the server code and you can fix those problems or report them to others.

The patch is for MySQL 5.1.26 and builds on x86_64 servers running Linux 2.6. It might not build elsewhere.

Or, “Missing information in the MySQL Manual”.

Just earlier today, I was using POW(), which I’ve grown quite fond of, simply because it makes life easier. I prefer using it like SELECT 512*POW(1024,2) to find out the number of bytes to put in a variable, for example.

First, let’s take a look at the POW function:

Name: 'POW'
Description:
Syntax:
POW(X,Y)

Returns the value of X raised to the power of Y.

Okay, so it gives us a value; but what about the data type? Let’s take 512*POW(1024,2) as an example.

5067 (blogs) > SELECT 512*POW(1024,2) AS example;
+-----------+
| example   |
+-----------+
| 536870912

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Having a status column is very common in databases today. It can be used to denote a user status: CREATE TABLE IF NOT EXISTS `user` ( `user_id` int(10) unsigned NOT NULL auto_increment, `email` varchar(32) NOT NULL, `pw_hash` char(40) NOT NULL COLLATE latin1_general_cs, `status` enum('PENDING', 'ACTIVE', 'DISABLED') default 'PENDING', `date_created` timestamp NOT NULL default CURRENT_TIMESTAMP, PRIMARY KEY (`user_id`), UNIQUE KEY `idx_email` (`email`) ); or user-uploaded [...]

I was trying to check out the new Zabbix beta's when I ran into a couple of problems. Mostly missing dependencies but also some bugs.

The big troubles start when trying to install the frontent.
It seems like php code shipped in the last release might well work when you are upgrading but it fails when you are doing a fresh install. As I never got a Setup Wizard.

The clue is to get the most recent code from their SVN repo svn co svn://svn.zabbix.com/trunk , that actually allows you to run the setup wizard.

If you are installing the latest RPM's they are also not really requiring all the dependencies you need to run the frontend.

yum/apt-get install php-bcmath php-pear

Will get you a step further.

Another thing is the new password policy.. it seems the Admin/blank is gone.
I have no clue what the new password is but you are encouraged to set it

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