… PXC for HP Cloud DNS. The post focuses on the key aspects of synchronous replication setup with high-availability guarantees like… reduced locking period from its use (which means the donor is blocked for a shorter while). By using Xtrabackup for SST, you also… like compression, parallel streaming, encryption, compact backups which can be used for SST (Note, the wsrep_sst_xtrabackup in 5.5…
Post: Percona XtraDB Cluster (PXC) in the real world: Share your use cases!
June 17, 2013 By Leave a Comment
Post: MySQL and the SSB - Part 2 - MyISAM vs InnoDB low concurrency
May 22, 2013 By Leave a Comment
… with default settings using only the InnoDB storage engine. In my testing I discovered that innodb_old_blocks_time had an effect… tests I used a 10GB key buffer. I used ALTER TABLE DISABLE KEYS and built the keys with sort via ALTER TABLE ENABLE KEYS. my.cnf…=32 innodb_old_blocks_time=0 table_open_cache=2048 table_definition_cache=16384 innodb_flush_method=O_DIRECT key_buffer_size…
Post: The small improvements of MySQL 5.6: Duplicate Index Detection
May 31, 2013 By Leave a Comment
… it would break 99% of all applications out there that use MySQL, for which we at Percona tend to find redundant….test # ######################################################################## # col2 is a left-prefix of col2_2 # Key definitions: # KEY `col2` (`col2`), # KEY `col2_2` (`col2`,`col3`) # Column types: # `col2` int… block directly all cases. A set of MySQL utilities were introduced by Oracle recently, which includes mysqlindexcheck, similar to pt-duplicate-key…
Post: Benchmarking Percona Server TokuDB vs InnoDB
May 7, 2013 By 32 Comments
…, which should produce updates in-place (I will use INSERT .. ON DUPLICATE KEY UPDATE statements for that), so it will produce all…)+k; COMMIT; So this workload produces SEQUENTIAL inserts into Primary Key, that this is quite suitable for InnoDB, and in it…_log_block_size=4096 #####plugin options innodb_read_io_threads = 16 innodb_write_io_threads = 4 innodb_io_capacity = 4000 innodb_use…
Post: Galera Flow Control in Percona XtraDB Cluster for MySQL
May 2, 2013 By 5 Comments
… should be taken for applications to avoid using Donor/Desynced nodes, particularly when using a blocking SST method like rsync or mysqldump. So… size of the transactions, which translates into number of unique key lookups into the certification index, which is a hash table… a large replication queue without flow control if they are blocked by the underlying SST method, i.e., by FLUSH TABLES…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
…_use_native_aioblogpercona.commanual innodb_use_…Key_blocks_not_flushedblogpercona.commanual Key_blocks_unusedblogpercona.commanual Key_blocks_usedblogpercona.commanual key_buffer_sizeblogpercona.commanual key_cache_age_thresholdblogpercona.commanual key_cache_block_sizeblogpercona.commanual key…
Post: How much overhead is caused by on disk temporary tables
August 16, 2007 By 26 Comments
… like “key%”; +————————+———+ | Variable_name | Value | +————————+———+ | Key_blocks_not_flushed | 6516 | | Key_blocks_unused | 0 | | Key_blocks_used | 7248 | | Key_read_requests | 2051451 | | Key_reads | 198208 | | Key_write_requests | 469220 | | Key_writes…
Post: To pack or not to pack - MyISAM Key compression
May 13, 2006 By 4 Comments
… details about packed keys and performance implications it causes. First lets see how key compression works. Key compression applies on the block boundaries – first… row lookup by index (ie joins) will also suffer as key block needs to be uncompressed for each of these Larger pages… compress string keys but not integer keys is the biggest reason joins using string keys is so much slower compared to integer keys. Integer keys still…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 28 Comments
…manual: Key_read_requestsThe number of requests to read a key block from the cache. Key_readsThe number of physical reads of a key block … useful you can do with Key_reads: [baron@localhost ~]$ mysqladmin ext -ri10 | grep Key_reads | Key_reads | 6030962 | | Key_reads | 98 | | Key_reads | 89 | | Key_…
Comment: MySQL Server Memory Usage
September 1, 2006 By 21 Comments
…’, ’292923929′ ‘Key_blocks_not_flushed’, ’0′ ‘Key_blocks_unused’, ’28987′ ‘Key_blocks_used‘, ’1332′ ‘Key_read_requests’, ’1552507′ ‘Key_reads’, ’1654′ ‘Key_write_requests’, ’114303′ ‘Key_writes’, ’1346′ ‘Max_used_connections’, ’651… interactive_timeout=3600 wait_timeout=3600 key_buffer_size=32M # Only for MyISAM which isnt used. sort_buffer_size=2M query_cache…
