… used a 10GB key buffer. I used ALTER TABLE DISABLE KEYS and built the keys with sort via ALTER TABLE ENABLE KEYS. my.cnf [mysqld…=2048 table_definition_cache=16384 innodb_flush_method=O_DIRECT key_buffer_size=10G # Disabling symbolic-links is recommended to prevent assorted security…
Comment: Percona XtraBackup 2.1.3 for MySQL available for download
May 30, 2013 By 3 Comments
… by reporting any bugs at http://bugs.percona.com/ key_buffer_size=52428800 read_buffer_size=131072 max_used_connections=13 max_threads=2002 thread… It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 4432877 K bytes of memory Hope that…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… covered in the first post: single SELECT queries doing PRIMARY KEY lookups (aka QPS sysbench mode); same MySQL queries executed inside… innodb_flush_method = O_DIRECT innodb_log_buffer_size = 16M innodb_buffer_pool_size = 52G innodb_log_file_size = 2000M innodb_log_files_in_group…
Post: Benchmarking Percona Server TokuDB vs InnoDB
May 7, 2013 By 32 Comments
…_table_size = 64M server-id = 10 #*** MyISAM Specific options key_buffer_size = 8M read_buffer_size = 1M read_rnd_buffer_size = 4M bulk_insert_buffer_size = 8M myisam_sort_buffer_size = 8M myisam_max_sort_file_size = 10G #myisam…
Post: Virident vCache vs. FlashCache: Part 2
May 17, 2013 By 3 Comments
…_cache_size = 0 query_cache_type = 0 ft_min_word_len = 4 thread_stack = 192K tmp_table_size = 64M serverid = 101 key_buffer_size = 8M read_buffer_size = 1M read_rnd_buffer_size = 4M bulk_insert_buffer_size = 8M myisam_sort_buffer_size = 8M myisam_max_sort_file_size…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 4 Comments
…=’mrr_cost_based=off’ optimizer_switch=’batched_key_access=on’ join_buffer_size=6M read_rnd_buffer_size=6M Also note that the following changes….5 w/ buffer size 6M MariaDB 5.5 (3) is for MariaDB 5.5 w/ buffer size 6M (Hash Join and Key-ordered Scan disabled….5 w/ join_buffer_size=6M & mrr_buffer_size=6M MariaDB 5.5 Hash Join Disabled w/ join_buffer_size=4M & mrr_buffer_size=4M Created_tmp_disk…
Post: What exactly is read_rnd_buffer_size
July 24, 2007 By 4 Comments
Looking for documentation for read_rnd_buffer_size you would find descriptions such as “The read_rnd_buffer_size is used after a sort… very similar to read_buffer_size which is currently only used by MyISAM tables I thought read_rnd_buffer_size is also MyISAM only… having only row pointers together with key value – which are offsets for MyISAM and primary key values for Innodb or storing full…
Post: How is join_buffer_size allocated?
July 5, 2010 By 9 Comments
… “max size” and the corresponding buffers are allocated only as big as needed (key_buffer_size). There are many examples of this. What about join_buffer_size? I saw a my.cnf with a 128M join_buffer_size the…
Post: Are larger buffers always better ?
June 6, 2006 By 9 Comments
… quite unexpected improvements. sort_buffer_size – recently I worked with case which was running much faster with 32K sort_buffer_size, compared to 32M…(10) default NULL, `d` int(11) default NULL, PRIMARY KEY (`id`), KEY `d` (`d`) ) ENGINE=MyISAM DEFAULT CHARSET=utf8 select sql_no…=50 and some 10 distinct c values. read_buffer_size and read_rnd_buffer_size – These are buffers used by MyISAM to perform reads, in…
Post: Some little known facts about Innodb Insert Buffer
January 13, 2009 By 12 Comments
… can be performed with single sweep. Insert buffer only can work for non-unique keys because until the merge is performed it is impossible to check if the value is unique. Insert buffer is… no unmerged records. The “size” is size (in pages) of insert buffer which is not merged. The fact size is in pages is not…
