June 20, 2013

Post: Benchmarking Percona Server TokuDB vs InnoDB

May 7, 2013 By 32 Comments

…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_max_extra_sort_file_size = 10G myisam…

Filed Under: Benchmarks, MySQL, Percona Server Tagged With: , , ,

Post: Virident vCache vs. FlashCache: Part 2

May 17, 2013 By 3 Comments

…used was Percona Server 5.5.30-rel30.1-465. Each test was allowed to run for…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_repair_threads = 1 myisam…

Filed Under: Benchmarks, Hardware and Storage, MySQL Tagged With: , , , , , , ,

Post: Impact of the sort buffer size in MySQL

October 25, 2010 By 8 Comments

… size of the sort_buffer. It is my understanding that the sort_buffer is used when no index are available to help the sorting so I created a MyISAM… time for the queries loses all dependency over the sort buffer size. I am still trying to figure out why the number of sort merge passes felt to…

Filed Under: Benchmarks, MySQL Tagged With: ,

Post: MySQL Server Variables - SQL layer or Storage Engine specific.

June 8, 2006 By 14 Comments

…for Full Table Scan (read_buffer) and for reading rows in sorted order (read_rnd_buffer_size). Other storage engines such as Innodb to not use this variable. sort_buffer_size Buffer used to sort…

Filed Under: Insight for DBAs Tagged With: ,

Post: MySQL 5.5 and MySQL 5.6 default variable values differences

February 21, 2013 By 8 Comments

…sort_buffer_size was decreased to 256K from 2M. This change should help many small sorts for which allocation of 2M for sort buffer…to create Innodb table but getting MyISAM because Innodb was disabled for…

Filed Under: Insight for DBAs, MySQL Tagged With: , , ,

Post: InnoDB Full-text Search in MySQL 5.6 (part 1)

February 26, 2013 By 1 Comment

…MyISAM; I would argue that in most situations, any possible advantages to using MyISAM…For now, the important number here is to note that the InnoDB buffer pool for my 5.6 instance is 128MB – smaller than the size…

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , ,

Post: MySQL: what read_buffer_size value is optimal ?

September 17, 2007 By 25 Comments

…sort performance and today I’ve discovered even read_buffer_size…MyISAM DEFAULT CHARSET=latin1 1 row in set (0.00 sec) Populated it with 75M of rows to reach 4G in size…size for read_buffer_size, this is why…

Filed Under: Benchmarks, Insight for DBAs Tagged With:

Post: Why MySQL could be slow with large tables ?

June 9, 2006 By 141 Comments

…Buffers, Indexes and Joins. Buffers First thing you need to…), multi-server partitioning to use combined memory and…for MyISAM tables. Now if we take the same hard drive for fully IO bound workload it will be able to… be placed in sorted way or pages placed…to disaster. The problem is not the data size …

Filed Under: Insight for DBAs Tagged With: ,

Post: table_cache negative scalability

November 16, 2009 By 23 Comments

…size also sort_buffer_size and read_buffer_size may not give you better performance if you increase them. I found this also applies to some other buffers… sync_frm option is used. With default table_cache=…to the disk during this read-only benchmark. Why ? Because for MyISAM tables table header has to…

Filed Under: Benchmarks Tagged With:

Post: Are larger buffers always better ?

June 6, 2006 By 9 Comments

…sort_buffer_size – recently I worked with case which was running much faster with 32K sort_buffer_size, compared to 32M. The problem was memory allocation – sorting was used…

Filed Under: Uncategorized Tagged With: , , , , , ,
« Older Posts