…Lets go over them: back_log = 50 + ( max_connections / 5 ) capped at 900 – The … just default at 2000 ? innodb_file_per_table =1 Great! We found it … more would be good default. query_cache_size = 1M Query cache remains off by default … we have in the phones these days, I made in my Optimizing MySQL …
Comment: MySQL 5.5 and MySQL 5.6 default variable values differences
February 21, 2013 By 8 Comments
… higher values are desirable at high connection rates. max_connections was the best proxy we had for …bigger size. A few passes per second or tens of passes per second at high query rates is likely to …an official Oracle view, consult a PR person. James Day, MySQL Senior Principal Support Engineer,…
Comment: table_cache negative scalability
April 14, 2010 By 23 Comments
…/mysql-bin expire_logs_days = 30 # Expire logs after in X days. long_query_time = 2 thread_cache_size = 100 max_connections = 400 table_cache = 20000 open_files_limit = 40000 max_binlog_size = 500M max… = 100M query_cache_size = 100M default_table_type = MYISAM log_long_format # Innodb innodb_status_file = 1 innodb_file_per_table = 1…
Comment: table_cache negative scalability
April 14, 2010 By 23 Comments
…/mysql-bin expire_logs_days = 30 # Expire logs after in X days. long_query_time = 2 thread_cache_size = 100 max_connections = 400 table_cache = 20000 open_files_limit = 40000 max_binlog_size = 500M max… = 100M query_cache_size = 100M default_table_type = MYISAM log_long_format # Innodb innodb_status_file = 1 innodb_file_per_table = 1…
Post: How is join_buffer_size allocated?
July 5, 2010 By 9 Comments
… join_buffer_size the other day and needed to research this … allocated per-thread (i.e. per-connection), this one is allocated per-join-per-thread,… because there’s no index. If the query joins several tables this way, …_ptr=0; /* End sequentel */ 14271 size=max(thd->variables.join_buff_size, cache->…
Post: Talking MySQL to Sphinx
April 19, 2009 By 4 Comments
… 10 rows in set (32.47 sec) MySQL mysql> select max(forum_id) as m,author_id as a …able to talk to MySQL these days. Now on performance – for given class of queries Sphinx was just 1….raw scan speed was almost 10 millions of rows per second (this is on rather outdated CPU I …
Comment: MySQL Server Memory Usage
September 1, 2006 By 21 Comments
… is how do you determine the memory consumption per connection in average? This leads to the next …’3′ ‘Uptime’, ’4433556′ # top 18:38:40 up 175 days, 2:56, 1 user, load average: 0.79, …/log log-slow-queries=/var/log/mysql/slow-queries.log max_connections=650 open_files_limit=6144 max_connect_errors=…
Post: How much memory can MySQL use in the worst case?
February 12, 2009 By 17 Comments
…buffer_size + (read_buffer_size + sort_buffer_size)*max_connections”. This was never true — not even when…remember. And at a minimum, most servers these days need to consider the added memory for InnoDB: … b ) as c; You can have many of those per query. Sorting and grouping and DISTINCT and UNION may…
Post: XtraDB/InnoDB CPU bound benchmarks on 24cores server
December 29, 2008 By 6 Comments
…size=1M max_allowed_packet=1M max_connections=3000 max_heap_table_size=64M max_prepared_stmt_count=1000000 query_cache… Based 24 Core Servers are not mainstream these days but as number of cores is increasing …” cases – but on other hand 64-128GB RAM per box is not something rare already and …
Post: MySQL Server Variables - SQL layer or Storage Engine specific.
June 8, 2006 By 14 Comments
… have really bulk inserts 100-1000+ values per single insert statement. concurrent_insert – Enables concurrent …in practice it is MyISAM related. expire_logs_days This is replication/binlogging related options – when… ft_boolean_syntax, ft_max_word_len, ft_min_word_len, ft_query_expansion_limit, ft_…
