…/ 168 F (Normal) Installed memory : 512 MB Copyback : Disabled Background consistency check : Disabled Automatic Failover : Enabled Global task priority : High Performance Mode… this controller per technical specs. If you would like to check the cache status it should be in the logical drive…
Post: Looking for RAID Controller without Battery Learning problems ?
January 5, 2012 By 11 Comments
Comment: Making replication a bit more reliable
March 6, 2009 By 14 Comments
Alex, I have run into similar duplicate key errors in the past. It turns out the slave I was using to take backups had slightly different data than the master. You may want to do a consistency check using Maatkit just to be sure.
Comment: 10 things you need to know about backup solutions for MySQL
March 4, 2009 By 23 Comments
… another server and started it there, with some simple data consistency checks. So please explain what inconsistencies or errors I should expect…
Comment: How reliable RAID really is
April 2, 2008 By 13 Comments
… state once the replacement drive starts rebuilding. I recommend a consistency check every month. RAID is absolutely NO substitute for a backup…
Post: How to recover a single InnoDB table from a Full Backup
January 25, 2012 By 10 Comments
… –export /tmp/ Then apply the logs to get a consistent backup: # innobackupex –defaults-file=/etc/my.cnf –apply-log –…mysql> ALTER TABLE salaries IMPORT TABLESPACE; mysql> set FOREIGN_KEY_CHECKS=1; mysql> SELECT * FROM salaries WHERE emp_no=10008; +——–+——–+————+————+ | …
Post: Make your file system error resilient
August 24, 2011 By 8 Comments
… systems like XFS will not continue if consistency problems are discovered. So how can you check what error behavior mode your file… to what you care the most – Do you care about consistency or availability ? Are you ready to risk for some data… solution. Maximum mount count: -1 and Check interval: 0 () These corresponds to automatic file system check on startup which is normally done…
Post: The story of one MySQL Upgrade
October 8, 2010 By 8 Comments
… we needed to do a sanity check on existing replication setup. As we’re checking replication consistency down the road we need to… is in sync. mk-table-checksum can use replication to check consistency but comparing 2 servers directly is faster and we had… years which could report different checksum in some cases. Rerunning check using BIT_XOR algorithm eliminated those false positives. Another table…
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
…modifications on that table. This makes reads consistent and therefore makes the replication between servers consistent. If you execute SELECT * FROM id… Disables the gap locks except for foreign-key constraint checking or duplicate-key checking. The most important difference between these two …
Post: Investigating MySQL Replication Latency in Percona XtraDB Cluster
March 3, 2013 By 13 Comments
… Latency in Percona XtraDB Cluster[/caption] I was curious to check how Percona XtraDB Cluster behaves when it comes to MySQL… different applications on the same cluster – some requiring better data consistency guarantees, other being OK with a little bit stale data… enable wsrep_causal_reads=1 option and get full data consistency. But what happens if we have some larger transactions ? To…
Post: How InnoDB handles REDO logging
February 3, 2011 By 19 Comments
… of data logged whilst still ensuring the log is action consistent and each operation is idempotent. It is important to note… needs to operate on consistent pages, Innodb achieves this by using the double write buffer to ensure consistent page writes. Why log… process updates is tightly linked to the speed at which check-pointing can occur. In order to insert a new record…
