…both incremental and full restores The …form of deadlock errors to the clients of affected transactions. Technically these aren’t necessarily deadlocks, but instead a cross-node locking conflict of… node1 mysql> SHOW ENGINE INNODB STATUS\G … ———— TRANSACTIONS ———— … —TRANSACTION…
Post: Percona XtraDB Cluster: Multi-node writing and Unexpected deadlocks
August 17, 2012 By 17 Comments
Post: Implementing efficient counters with MySQL
July 1, 2007 By 16 Comments
… some form of caching, ie memcache you end up reducing number of reads from database dramatically but writes still have to happen at full… rows even for Innodb tables which makes it 200MB in total which easily fits in buffer pool. Fitting of the working set… problem to deal with is log flushes. If you have innodb_flush_log_at_trx_commit=0 or 2 or if…
Post: Understanding Multi-node writing conflict metrics in Percona XtraDB Cluster and Galera
November 20, 2012 By 17 Comments
…The magic of Galera replication The short of it is that Galera replication is not a doing a full 2-… the rest of the cluster a writeset didn’t pass certification (or this would be a form of two-… error happens (which shouldn’t happen in normal Innodb), the transaction is rolled back, and this counter …
Post: 3 ways MySQL uses indexes
September 12, 2009 By 28 Comments
…of BTREE index is – it allows to retrieve data in sorted form hence avoiding external sort process for executing of… to use index for sort if you sort full table without a limit). However ORDER BY B…index to read data Some storage engines (MyISAM and Innodb included) can also use index to read the …
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
… key constraint is incorrectly formed What is also interesting is – this error 150 is in fact internal Innodb error code. Other storage… from consistent. Let me give you another example. So Innodb has limit of 1023 open transactions which perform writes. I’m not… (HY000): The table ‘yt’ is full For me table is full means something like I’m out of disk space (or quota set…
Post: Migrating to XtraDB Cluster Webinar follow up questions
June 6, 2012 By 3 Comments
… in an xtradb cluster to take your full and incremental backups of the cluster’s databases? Well, if …SST does not work with rsync when the option innodb_data_home_dir is set to a different … suggest pt-online-schema-change. Q: Does replication of MyISAM form any bottlenecks in XtraDB Cluster? If so, …
Post: A case for MariaDB's Hash Joins
May 31, 2012 By Leave a Comment
…for joining tables that have a equijoin conditions of the form tbl1.col1 = tbl2.col1, etc. As …innodb_file_per_table=1 innodb_file_format=barracuda innodb_log_file_size=512M innodb_log_files_in_group=2 innodb… with no indexes on the join condition (Full Join). The best performance with Hash Join …
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
…Form Factor Type Type Detail ========= ======== ================= ============= ============= =========== DIMM_A1 4096 MB 1333 MHz (0.8 ns) DIMM {OUT OF… using full partition …innodb_flush_method = O_DIRECT innodb_log_buffer_size = 8M innodb_buffer_pool_size = 128M innodb_log_file_size = 64M innodb…
Post: Recover BLOB fields
July 1, 2010 By 4 Comments
… 7k) then the full record is stored in the page of PRIMARY index. Let’s call it internal. In InnoDB sources they have… BTR_EXTERN_PAGE_NO is FIL_NULL. Percona InnoDB Recovery Tool supports now recovery of long fields. It is still in development… tab-separated values format. BLOBs are printed in a hex form – 0ACD86… To upload the table back you should utilize UNHEX…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 28 Comments
…all the information you need to form an opinion, right? Instead of asking the same annoying question, let…of storage engines (some InnoDB, some MyISAM, which is more important to you, etc) and choose an amount of… key_buffer_size until, when the buffer is full, Key_reads/Uptime reduces to a number you…
