Since starting the innotop and mysqltoolkit projects on Sourceforge, I have learned a lot about how to use source control more effectively – especially how branching and tagging can be used. Still, I have limited experience. I want to package all the tools in MySQL Toolkit together and release them in one archive, but I don’t know the best way to do it; every idea seems to have drawbacks. Read on for the details, and if you have suggestions, would you please leave comments for me?

MySQL Table Checksum 1.1.6 enhances chunking, adds features and fixes bugs. The chunking functionality is where I continue to put most of my effort. This release’s behavior is incompatible with the last release, and it will probably change again in the future. Thanks to everyone who has been helping me chase down bugs, including one user who sent me a major patch! It’s a great feeling to get a patch.

The other day I blogged about the fact that I thought partitioning was broken in 5.1.18.

There does in fact appear a bug that was introduced somewhere between 5.1.17 and 5.1.18 which is causing MySQL to dump core.

I tried recompiling 5.1.18 from source and the problem remained. Installing a 5.1.17 source build fixed the problem and we’ve been online for almost 72 hours without a core dump. By way of comparison 5.1.18 wouldn’t stan up for more than a few hours.

I’m not sure I have a ton of time to debug the issue but I wanted to get the information out into the public.

Assumptions:

RHEL
x86_64
EXT3
RAID

What Raid to use?
RAID-10

Why?
It's faster. RAID-5 offers more disk space but the parity bit messes things up, unless you have some uber hardware-raid card that caches that operation. Personally I am not a fan.


Stripe Size:
128K - this is really good for INNODB, you'll see a huge boost in responsiveness by making your Stripe Size 128K. I had a 64K stripe size, and I was blown away by the improvement of 128K


Mount options:

mkfs.ext3 -T largefile | mkfs.ext3 -T largefile4

Unless your going to have millions of files, this is a good option.


Make sure /etc/fstab mounts the mysql partition or the data that mysql resides on with noatime.

atime is accesstime: this is a huge boost in performance, tracking each time …

Ok, so I knew about innodb_table_monitor and innodb_tablespace_monitor. I’ve tried them before, looked at the output and given up, partly because it didn’t serve the purpose I wanted it to at the time, and also because it’s format was a little cryptic.

What I didn’t know was there are actually 4 monitors via this “create table functionality”. You can also do innodb_monitor which is the same as SHOW INNODB STATUS, and you can also do innodb_lock_monitor .

Another thing I didn’t know is that these commands don’t send the output just once, it’s on a timer. I’ve found the timers to be different. For innodb_monitor you get every 15 sec, as well as a nice line given time of averages which seems to always say 16 seconds.

=====================================
070601 15:11:25 INNODB MONITOR OUTPUT
=====================================
Per …

I've been looking through the Fedora Core 7 release notes this morning. One thing which stood out was their inclusion of Smolt.

Smolt is a hardware profiler which sends out put back to a public webserver being run by Redhat. Turn it on, and Redhat can see what hardware you are running. This type of phone home service is one that we have talked about for a long time at MySQL.

Would users be open to us sending back non private data about their systems? OS, machine type, config parameters, storage engines used... information found in show variables. What is the level of detail?

Would any detail be too much? Even if the code laid dormant unless turned on, what would users think?

I'm happy to see one of the open source vendors take this leap. I think open information like this is great, since it allows software writers to …

In a previous post, I mentioned the availability of the dtrace extension for Cool Stack's PHP.  Using this extension and the Cool Stack MySQL, it is possible to analyze the performance of your application running on this stack. At JavaOne, we demoed this using the open source MediaWiki and SugarCRM applications.  dtrace is especially useful in analyzing complex multi-tier applications like AMP. Thanks to Angelo Rajadurai for the creation of the scripts that I describe below.

Analyzing PHP calls

So, let's look at a simple dtrace script that counts how many times a particular PHP function is called :

#!/usr/sbin/dtrace -Zqs

php*:::function-entry
/arg0/
{
        @[copyinstr(arg0)]=count();
}

You can copy the …

I've been following the comments to Jamie's latest post and I have to say that most of the people who left comments are not thinking logically about this.  Most (not all) are outraged that Microsoft would try to prevent Jamie from enabling his most excellent TestDriven.Net product on the Express line of products (Visual C# Express, etc).

As a consumer I would love to be able to use plugins in the Express products.  I use Visual C++ Express to code on the MySQL server frequently.  However, I'm smart enough to realize when I've been given something for free. Let me say this slowly and clearly:  Microsoft is a business, not a public service.  They didn't have to make the Express products available at all.  It takes a great deal of time and money to build something as complicated as these …

Ronald Bradford has published the 47th edition of Log Buffer, the weekly review of database blogs, on Technical Notes and Articles of Interest. Get in touch if you’d like to edit and host an edition of Log Buffer on your own blog. The Pythian Group Blog is widely read, so being a part of the [...]

Log Buffer #47: a Carnival of the Vanities for DBAs
June 1st, 2007 - by Ronald Bradford

Welcome to the 47th edition of Log Buffer, the weekly review of database blogs. No time to wait, lets read more about this week’s database blogging activities.

The PostgreSQL Conference for Users and Developers wrapped up this week and Peter Eisentraut gives us a review including the lightning talks and wrap-up session with a charity auction in PGCon Day 4. Meanwhile Alex Gorbachev is at Miracle Scotland Database Forum - Day One, sounds like from his post there is a lot …