The only issue we've had is with replication. It seems to bomb out and we had to cron a restart task to keep it up. I don't know if this is a problem because the master is running 5.0 and the slave is running 5.1. The bug list is still kinda long on replication too.

Other than the cron job hack, no issues to report.

I just sent this to support before I discovered this topic:

"I have the following system:

Centos 5.5
64 bit
Plesk 9.5.2

I succesfully upgraded to MySQL 5.1.47 using:

yum --enablerepo=atomic-testing upgrade mysql

Everything seemed to work flawlessly except when I used Plesk's phpMyAdmin to view the databases.

It listed the following error:

'Your PHP MySQL library version 5.0.90 differs from your MySQL server version 5.1.47. This may cause unpredictable behavior.'"

Parallels website states:

"Plesk panel itself uses separate apache server copy with other compiled-in PHP"

Therefore, is this going to potentially cause problems whenever you use Plesk Panel?
i.e. Plesk will be administering a MySQL 5.1 database using 5.0 client libraries.

There is nothing you can do about that as your OS is native mysql-5.0 and parallels always build against stable or testing packages. The only way to fix that is to use an OS like Fedora 11 that as native mysql-5.1

But its not an issue, I have a client who has a Fedora 7 (yes 7!) server he just sticks with. I backported and bult my own compat-libraries and its been running mysql-5.1 since about mysql 5.1.10 odd.

Its nothing to worry about the compat-libraries bridge the client and server.

Thank you aus-city. I understand after your explanation.

In that case:

mysqlclient15-5.0.90-1.el5.art.x86_64.rpm

in the atomic testing repository must actually be using compat-libraries so that with PHP, you can connect to a MySQL 5.0 or 5.1 server without issue. (The PHPMyAdmin "error" message stating that the PHP MySQL library version and MySQL server version then becomes completely irrelevant).

Can this please be confirmed.

Yes that is correct

The mysqlclient15 is simply a bridge in the sql libraries. Plesk is looking for the 5.0 libraries (the actual .so library files that its been compiled against).

If you simply try to update mysql from 5.0 to 5.1, these so.5.0 library files are removed and replaced with 5.1.so library files, hence the dependency error against anything compiled against the mysql-5.0-devel package.

This then breaks plesk as its now got missing so libraries it needs (if you were to force the update), as it can't find the 5.0.so libraries.

This is why sometimes when you remove one package, more get pulled as those share libraries themselves.

Anyway in this case the mysqlclient15 package simply is a cut down mysql-5.0 package only containing these libraries (the 5.0 ones) that are needed.

The mysql-5.1 is built having the mysqlclient15 as a dependency so this just happens nicely so it updates without issues.

So plesk is happy as it still has its libraries its compiled against.

So it will always say in the plesk gui on phpmyadmin the 5.0.90 client or say a 91 or 92 if 5.0 was continuing to be built and updated, but since 5.0 is no longer amintained it will stay at 5.0.90.

The only way to ever fix this is to recompile the actual plesk packages against a mysql-5.1-devel, but parallels will not do this as if the 5.1 is not officially released anyone not running the later mysql would have their system break.

Unfortunately its a common issue with updating packages not in the OS, you may have to add compatibility libraries, or rebuild 10 packages as these all have dependency issues.

Hope that explains it better for you.

Part of this has to do with how open source works in general. People are always putting out new versions of everything you use, from kernels to web servers to databases. As such, Linux, several years ago, was a morass of hodge-podge builds featuring everything and anything. Some people were running older, some newer, and some different software entirely. As such, trying to write software for Linux was a nightmare of patchy support. Enterprise Linux (RHEL and CentOS) changed this by locking in what was being used at the core. So everyone running EL5, for instance, has the same version of Apache. The problem of security patches was dealt with by backporting fixes into the fixed version. So EL5 is built around MySQL 5.0 and everything designed for it works with that.

From a practical standpoint, however, not everything can be that static. If it were, we'd still all be running PHP 5.1 (which is what EL5 shipped with). Hence there's repos like atomic, where you can get newer (if unsupported) versions. Technically nobody has to go to mysql 5.1 but, if you need some of the new features, you might not have that luxury. But trying to upgrade libraries is probably more trouble than it's worth.

EL6 has 5.1 built in. But EL6 won't be commercially available, let alone available as C6, until late this year. I'd say C6 will be Q1 2011 at the earliest. It will likely be a few months after that that Plesk begins to support 5.1.

Understood and I agree, that's what makes the Atomic Repository so great.

If there is a requirement for a newer version of software available in the repository, it makes things so much easier. And even though technically officially unsupported, I haven't had any trouble with anything that I've installed from the Atomic repository.

I needed some of the features of MySQL 5.1, so I couldn't stay with MySQL 5.0.

In any case, this topic started out by reporting any issues with MySQL 5.1.43

After this discussion, thank you for all comments which addressed my concerns, I can say I've upgraded to MySQL 5.1.47 without issue and everything's working great.

Due to a recently found problem with one of our tables, high traffic and innodb (and the fact that mysql only fixed this bug for 5.1), I'm probably going to roll my live database server up to 5.1 next week. Still no major problems (not inside Scott's power anyways) to report.

And with that note, the last nail is in the coffin of Mysql 5.0. 5.1.47 is being pushed out to all mirrors as we speak. From here on out atomic will be standardized on 5.1.x

Thanks for the reports everyone, I realize this is a fairly big change which is why it took so long.