…on this completely because InnoDB uses a clustered index based on (in order) the primary…etc. Read more in my > Why MySQL Could be slow with Large Tables article. Deciding …queries, especially > if you see them in slow query log. If you have trouble understanding > EXPLAIN or optimizing your queries…
Post: Commodity Hardware, Commodity Software and Commodity People
June 15, 2007 By 9 Comments
… solution for absolute beginner. Now from queries design MySQL would support a lot of functions (which… great MySQL Expert but have no experience with MySQL Cluster, other may be good with MySQL Cluster but have… also why old products become feature overkill, slow and complicated. I’m not in positions…
Post: Introducing our Percona Live speakers
May 10, 2011 By 4 Comments
… speakers, which is why it has been a slow process to finalize and get abstracts on the web… about using MySQL to find the top N most important rows per group of rows, distributed across a cluster …temp tables and filesorts and multiple queries and all sorts of things in MySQL — and that’s just for …
Post: The perils of uniform hardware and RAID auto-learn cycles
November 16, 2010 By 16 Comments
… selected machines on a large cluster of quite uniform database servers. Some of the servers were slowing down in a very puzzling way over a short time span (a couple of hours). Queries were taking… some threshold. I’ve seen this before — for example, a query cache bottleneck, or an insert buffer bottleneck, or any of…
Post: Read/Write Splitting with PHP Webinar Questions Followup
January 23, 2013 By 4 Comments
…MySQL asynchronous replication. edit: PXC is really a bit like semi-synchronous replication, in that changes are queued on all cluster… the MySQL database for persistence, but when we measured query load with pt-query-digest,… network between master and slave is slow or unreliable. A solution to …
Post: Improved InnoDB fast index creation
November 6, 2011 By 4 Comments
…mysql> SET profiling=1; Query OK, 0 rows affected (0.00 sec) mysql> ALTER TABLE t ADD COLUMN v VARCHAR(1); Query…” part will not be affected by a slow tmpdir, but rebuilding the indexes will obviously take… an index as the clustered one. References: Peter’s post MySQL bug #57583 MySQL bug #49120 Fast …
Post: Are you designing IO bound or CPU bound application ?
December 20, 2006 By 10 Comments
…and obvious but it is extremely important for MySQL Performance Optimization. In fact I probably have …can be extremely slow if it does not. For example if you have the query which analyzes …for ORDER BY .. LIMIT. For IO bound applications Clustering (data locality) also becomes very important – if …
Post: Recovery after DROP & CREATE
August 22, 2012 By 1 Comment
… CHARSET=utf8; Query OK, 0 rows affected (0.56 sec) # ./page_parser -f /var/lib/mysql/ibdata1 # ./bin…(`NAME`, `ID`, `N_COLS`, `TYPE`, `MIX_ID`, `MIX_LEN`, `CLUSTER_NAME`, `SPACE`); # If index_id is unknown there… assumes a lot of manual work and thus slow There is no way to differentiate tables based…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
… index reserves different extents from the clustered index. Q4: Does Innodb ever merges… if they were not matched by query where clause when it was not…having to seek on disk which slows down throughput. If we could control…ha_innodb.cc in 5.1: static MYSQL_SYSVAR_ULONG(thread_concurrency, srv_thread_…
Post: Should you move from MyISAM to Innodb ?
January 12, 2009 By 59 Comments
…slave available for all long reporting queries. In case MyISAM was chosen … the benefits side we usually see clustering by primary key, caching data, higher… with very large number of tables, slow data load and ALTER TABLE and…not so common paths in the MySQL server – in particular Optimizer may …
