Unintentional Googlewhack Leads to MySQL Bug Report
While doing a standard audit for a new client, I recommended a few changes to get better performance. Because I had several changes, I used the documentation at
http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html
and found that innodb_flush_log_at_trx_commit is a dynamic variable. I was surprised, because most operations dealing with file sizes and operations are not dynamic. But the client proceeded with:
set global innodb_flush_log_at_trx_commit = 2;
and got:
ERROR 1193 (HY000): Unknown system variable 'innodb_flush_log_at_trx_commit'
So I searched for others who may have had the same error, and ended up getting an unintentional googlewhack. Well, it’s not a real Googlewhack, because it has more than 2 words and I used quotes to surround it — but I was pretty surprised that there were not a lot more people like me who trusted the manual. Granted, it’s “intuitive” that the variable is one that would need a restart….but because I was looking up others, I just looked up all of them, and thus fell into the trap.
The search I did was “Unknown system variable innodb_flush_log_at_trx_commit”
And the bug I filed is http://bugs.mysql.com/bug.php?id=35575.
Category: Group Blog Posts, MySQL, Non-Tech Articles
Tags: documentation, dynamic, MySQL, static
Actually it is a dynamic variable, at least in later versions of 5.0.x — I use this whenever I reboot a server that is running on 2, dynamically set to 1 before the reboot to prevent data loss.
Verified on 5.0.45 and 5.0.46
[...] Unintentional Googlewhack Leads to MySQL Bug Report [...]
This post saved my life! I just *knew* I was going to restart my database to make this change, because nothing I could find in the docs say this can be done on the fly. Thanks for the post!