I occasionally see customers who are taking backups from their PXC clusters that complain that the cluster “stalls” during the backup. As I wrote about in a previous blog post, often these stalls are really just Flow Control. But why would a backup cause Flow control? Most backups I know of (even Percona XtraBackup) take […]
Thanks to everyone who attended last week’s webinar on MySQL security; hopefully you’ve all gone out and set SELinux to enforcing mode if you weren’t already running that way. If you weren’t able to attend, the recording and slides are available for viewing/download. But now, without further ado, here are the questions which we didn’t […]
Percona is glad to announce the release of Percona XtraBackup 2.0.5 on January 23rd, 2012. Downloads are available from our download site here and Percona Software Repositories. This release is the current GA (Generally Available) stable release in the 2.0 series. New Features: New option –defaults-extra-file has been introduced. This option specifies from what extra file to read […]
Ever ran into a situation where you saw “some important variable you really needed to know about=<optimized out>” while debugging?
Suppose you have turned on innodb_file_per_table (which means that each table has its own tablespace), and you have to drop tables in a background every hour or every day. If its once every day then you can probably schedule the table dropping process to run during off-peak hours. But I have seen cases where the […]
Many people use mysqldump –single-transaction to get consistent backup for their Innodb tables without making database read only. In most cases it works, but did you know there are some cases when you can get table entirely missing from the backup if you use this technique ? The problem comes from the fact how MySQL’s […]
I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the Percona documentation or forums. So I present to you what is now my newest Firefox toolbar bookmark: an option and […]
Following on from our earlier announcement, Paul McCullagh has responded with the answers to your questions – as well as a few I gathered from other Percona folks, and attendees of OpenSQL Camp. Thank you Paul! Whatâ€™s the “ideal” use case for the PBXT engine, and how does it compare in performance? Â When would I […]
It is a known fact that ext3 is not the most efficient file system out there and for example file removals can be painfully slow and cause a lot of random I/O. However, as it turns out, it can sometimes have a much more severe impact on the MySQL performance that it would seem. When […]
I am happy to announce next build of our backup tool. This version contains several bugfixes and introduces initial implementation of incremental backup. Incremental backup works in next way. When you do regular backup, at the end of procedure you can see output:
The latest check point (for incremental): '1319:813219999'
>> log scanned up to (1319 813701532)
Transaction log of lsn (1318 3034677302) to (1319 813701532) was copied.
090404 06:03:29 innobackupex: All tables unlocked
090404 06:03:29 innobackupex: Connection to database server closed
innobackupex: Backup created in directory '/mnt/data/tmp'
innobackupex: MySQL binlog position: filename 'db02-bin.001271', position 247627478
090404 06:07:58 innobackupex: innobackup completed OK!
innobackupex: You must use -i (--ignore-zeros) option for extraction of the tar stream.
which gives start point 1319:813219999 for further incremental backup. This point […]