In this post I will describe a non-trivial way to authenticate users in Percona Sever. Percona Server comes with PAM authentication plugin, which allows you to do a lot of cool things, such as: OS authentication, LDAP authentication, even RSA Secure Server authentication (which is useful if you are required a PCI-compliance), and use Google Authenticator, which is the topic of this post.
The third performance test I am doing compares MySQL 5.6 (5.6.10) with MySQL 5.1 for an update-only workload with an IO-bound database. The configuration is similar to what I used for the IO-bound & read-only tests. The performance summary is that for my test servers:
Most of the time, when people say “scalability” they mean any of dozens of things. Most of the time, when I say it I mean exactly one precisely defined thing. However, I don’t claim that’s the only correct use of “scalability.” There is another, in particular, that I think is very important to understand: the inherent limitations of the system. This second one doesn’t have a single mathematical definition, but it’s vital nonetheless.
I’ll frame the discussion by asking this: how scalable is your database?
SCaLE 11x’s MySQL track featured standing room only crowds on subjects from Beginning SQL, Indexes, HA, Credit Card Storage for PCI compliance, 5.6 new features, and how to solve Rubik cube-like puzzles with MySQL. Saturday and Sunday, we are Booth 71 and we are sharing the booth with the Los Angeles MySQL Users group. Come see MySQL 5.6 and workbench, get registered for the Virtual Developer Day, or just to say ‘hi’.
CentOS 5.8 and earlier use Perl module DBD::mysql v3.0007 which has a bug that causes Perl not to flag UTF-8 data as being UTF-8. Presuming that the MySQL table/column is using UTF-8, and the Perl MySQL connection is also using UTF-8, then a correct system returns:
A lot of work was done to make InnoDB faster for MySQL 5.6. The results are especially obvious for IO-bound read-only workloads. I have many performance tests to run and started with the easy ones. Yesterday I published results for a cached read-only workload and found a few problems that can and should be fixed (bugs 66473 & 68413).
As the part of analyzing surprising MySQL 5.5 vs 5.6 performance results I’ve been looking at changes to default variable values. To do that I’ve loaded the values from MySQL 5.5.30 and 5.6.10 to the different tables and ran the query:
Lately we’ve had many reports of the RPM packages for CentOS 5 (mostly) and CentOS 6 having issues when installing different combinations of our products, particularly with Percona Toolkit. Examples of bugs related to these issues are lp:1031427 and lp:1051874.
Had a case recently where I had to merge data from two identically structured tables containing nearly identical data.
"Nearly identical" meaning most table data is identical in both; sometimes a row is missing from one of the tables; sometimes same row (according to PK) appears in both, but some columns are NULL is one tables (while others can be NULL in the second).
Otherwise no contradicting data: it was not possible for some data to be "3" in one table and "4" in the other.