More on Studying MySQL Hashes in gdb, and How P_S Code May Help
I have to get back to the topic of checking user variables in gdb to clarify few more details. In his commentShane Bester kindly noted that calling functions defined in MySQL code is not going to work...
View ArticleFun with Bugs #55 - On Some Public Bugs Fixed in MySQL 8.0.2
I do not care much about MySQL 8.0.x at the moment, as it's far from being GA and is work in progress. It is not yet used by customers whom I have to support. But I know about many interesting changes...
View ArticleMySQL Support Engineer's Chronicles, Issue #8
This week is special and full of anniversaries for me. This week 5 years ago I left Oracle behind and joined Percona... Same week 5 years ago I had written something about MySQL in this blog for the...
View ArticleFun with Bugs #56 - On Some Public Bugs Fixed in MySQL 5.7.20
While MySQL 8.0.x hardly has much impact on my regular work, recent MySQL 5.7.20 release is something to check carefully. MySQL 5.7 is widely used in production, as a base for Percona Server 5.7, some...
View ArticleFun with Bugs #57 - On MySQL Bug Reports I am Subscribed to, Part I
I've decided to stop reviewing MySQL Release Notes in this series, but it does not mean that I am not interested in MySQL bugs any more. At the moment I am subscribed to 91 active MySQL bugs reported...
View ArticleHow lsof Utility May Help MySQL DBAs
While working in Support, I noticed that probably at least once a week I have to use or mention lsof utility in some context. This week, for example, we had a customer trying to find out if his mysqld...
View ArticleUsing strace for MySQL Troubleshooting
I'd say that strace utility is even more useful for MySQL DBAs than lsof. Basically, it is a useful general purpose diagnostic and debugging tool for tracing system calls some process makes and signals...
View ArticleFun with Bugs #58 - Bug of the Day From @mysqlbugs
In 2013 I had a habit of writing about MySQL bugs on Facebook almost every day. Typical post looked like this one, link to the bug and few words of wondering with a bit of sarcasm.By the way, check...
View ArticleFun with Bugs #59 - On MySQL Bug Reports I am Subscribed to, Part II
New Year (that starts on Monday!) gives a good opportunity to change something in our lives, start doing something new, better or different. Let's assume I failed with all these so far, as I am again...
View ArticleFun with Bugs #60 - On Some Memory Leaks, Replication and Other Bugs Fixed in...
Oracle had formally released MySQL 5.7.21 yesterday. I do not bother any more to study MySQL release notes carefully and completely, but during a quick review today I've noted several interesting items...
View ArticleOn InnoDB's Persistent Optimizer Statistics
As I put it in recent Facebook post, one of MySQL features that I truly hate is InnoDB's persistent statistics. I think I should clarify this statement. It's great to have a way to save statistics in...
View ArticleOn InnoDB's Online DDL
I am completing my preparations for the upcoming FOSDEM talk, and one of last things I wanted to do in frames of them is a quick review of known bugs and problems in current (as in MySQL 5.7 GA)...
View ArticleFun with Bugs #61 - On MySQL Bug Reports I am Subscribed to, Part III
Since my previous post on this topic I've subscribed to 19 more MySQL bugs, so it's time for yet another review of these reports. I am trying to pick up important, funny or hard to process reports...
View ArticleOn InnoDB's FULLTEXT Indexes
I had recently written about InnoDB features that I try to avoid by all means if not hate: "online" DDL and persistent optimizer statistics. Time to add one more to the list - FULLTEXT indexes.This...
View ArticleChecking User Threads With gdb in MySQL 5.7+
In one of my gdb-related posts last year I noted that there is no more simple global list of user threads in MySQL 5.7+:"I had highlighted Global_THD_manager singleton also as during my next gdb...
View ArticleFun With Bugs #62 - On Bugs Related to JSON Support in MySQL
Comparing to "online ALTER" or FULLTEXT indexes in InnoDB, I am not that much exposed to using JSON in MySQL. OK, there is EXPLAIN ... FORMAT=JSON statement that is quite useful, optimizer trace in...
View ArticleFun with Bugs #63 - On Bugs Detected by ASan
Among other things Geir Hoydalsvik stated in his nice post yesterday: "We’ve fixed a number of bugs detected by UBsan and Asan."This is indeed true, I already noted many related bugs fixed in recent...
View ArticleWindows Tools for MySQL DBAs: Basic Minidump Analysis
"To a man with a hammer, everything looks like a nail."Even though I had written many posts explaining the use of gdb for various MySQL-related tasks, I have to use other OS level troubleshooting tools...
View ArticleFun with Bugs #64 - On MySQL Bug Reports I am Subscribed to, Part IV
I've subscribed to more than 15 new MySQL bug reports since the previous post in this series, so it's time for a new one. I am trying to follow important, funny or hard to process bug reports every...
View ArticleFun with Bugs #65 - On MySQL Bug Reports I am Subscribed to, Part V
I think it's time to review some bugs I've subscribed to several months ago, those older than in the first post from this series. There are several really serious bugs in the list of 15 below:Bug...
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