…innodb_use_native_aioblogpercona.commanual innodb_use_sys_mallocblogpercona.commanual innodb_versionblogpercona.commanual innodb_write_io_threadsblogpercona.commanual insert_idblogpercona.commanual interactive_timeoutblogpercona.commanual join_buffer…
Post: MySQL 5.5 and MySQL 5.6 default variable values differences
February 21, 2013 By 8 Comments
…/dist/mysql-5.5.30-linux2.6-x86_ | /mnt/nfs/dist/mysql-5.6.10-linux-glibc2. | | MAX_ALLOWED_PACKET | 1048576 | 4194304 | | JOIN_BUFFER_SIZE… now allowing MySQL to handle larger queries. Makes sense as amount of memory available is much larger these days. join_buffer_size have been… have been when you have large number of tables or if you do many create/drop of innodb tables. optimizer_switch is the catch…
Post: Review of MySQL 5.6 Defaults Changes
October 8, 2012 By 10 Comments
…innodb_file_per_table =1 Great! We found it is better choice in 95%+ of installations innodb_log_file_size…and complicated queries efficiently automatically. join_buffer_size = 256k The default is …large etc referring to amounts of memory we have in the phones these days, I made in my Optimizing MySQL…
Post: A case for MariaDB's Hash Joins
May 31, 2012 By Leave a Comment
…’ join_buffer_size=32M MariaDB 5.5.20 Configuration innodb_file_per_table=1 innodb_file_format=barracuda innodb_log_file_size=512M innodb_log_files_in_group=2 innodb… as compared to BKA algorithm of MySQL 5.6. Test Case C – Join a small table with a large table with a WHERE clause on…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 4 Comments
…MySQL 5.5 MySQL 5.6 MySQL 5.6 w/ join_buffer_size=6M & read_rnd_buffer_size=6M MariaDB 5.5 MariaDB 5.5 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_tables…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…buffer size is large enough only a single range lookup will be needed, however if the buffer size is small as compared to the combined size…MySQL 5.6 w/ read_rnd_bufer_size=4M MariaDB 5.5 MariaDB 5.5 w/ mrr_buffer_size=4M Created_tmp_disk_tables…
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
…tables these are MyISAM related. join_buffer_size Buffer used for joins…buffer for MyISAM tables for Full Table Scan (read_buffer) and for reading rows in sorted order (read_rnd_buffer_size). Other storage engines such as Innodb…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…innodb-thread-concurrency=0 innodb-thread-concurrency-timer-based innodb-thread-sleep-delay=0 innodb-use-sys-stats-table innodb-write-io-threads=4 join-buffer-size=16M key-buffer-size…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 141 Comments
… very large data sets are Buffers, Indexes and Joins. Buffers …size and expect gradual performance decrease as database size…also clustered keys in Innodb which combine index …join of few large tables, which is completely disk bound can be very slow. One of the reasons elevating this problem in MySQL…
Post: MySQL Indexing Best Practices: Webinar Questions Followup
August 16, 2012 By 4 Comments
…buffer will not be able to be used, which can be important for large, heavily written tables…join the two tables? A: The question in this case is how MySQL will execute the join…
