… to execute and 29.9 sec for MonetDB, but it’s almost single case …Query execution So I really have data for InfoBright and MonetDB, let see how fast they are in different queries. First favorite query… note that MonetDB supports all INSERT / UPDATE / DELETE statements (and space is price for that as…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…, undo log entries 1 MySQL thread id 9697561, query id 188161264 localhost root update insert into child values(2,2) Foreign key constraint… and single page – independent page writes. We can also see number of pages being read and written. Created pages is empty pages created in…
Post: Fighting MySQL Replication Lag
September 22, 2008 By 7 Comments
… single threaded, which means if you have any long running write query it clogs replication stream and small and fast updates which go after it in… of values per batch in multiple row insert statement or Fetching data you’re planning to update/delete and having multiple queries to delete it…. It is crippled by having to do all of this in single thread already – do not make it even harder. If there…
Post: Innodb performance gotcha w Larger queries.
August 28, 2009 By 7 Comments
…update performance for the application and I was replacing single value UPDATE with multiple value REPLACE (though I also saw the same problem with INSERT…in 12 seconds for 1000 rows in a batch vs 40 seconds for single row statements. So with single… trx->mysql_query_str) { /* Scan the MySQL query …
Post: MySQL File System Fragmentation Benchmarks
March 21, 2008 By 28 Comments
…queries are going to be affected same way, for example point select reading single… in single tablespace mode showed following results: [root@DB10 ~]# for i in 1 …Insert performance is close, the difference is perhaps explained by the fact files needed to be constantly extended (meta data updates) and…
Post: Distributed Set Processing with Shard-Query
May 14, 2011 By 27 Comments
…INSERT-only workloads, and their are other optimizations that can be applied to views that are based on only a single…UPDATE is the same. All of the fastest incremental materialized view optimizations can be applied. Shard-Query works only on sets Shard-Query…MAX are only distributable in INSERT-only …
Post: High-Performance Click Analysis with MySQL
December 22, 2008 By 13 Comments
…and if the many rows don’t match completely, the single one doesn’t know what data should live in it. And… it on the master with INSERT..SELECT queries, it will propagate to the slaves and it’ll be hard… kind of emulates row-based replication in a way. When you’re updating big aggregate tables, don’t…
Post: Read/Write Splitting with PHP Webinar Questions Followup
January 23, 2013 By 4 Comments
…they would be in single-threaded MySQL replication. Therefore all nodes stay in sync much more… (updates,inserts) on multiple MySQL servers? Or is it possible to split only read queries (select… Training classes in North America and Europe. Join Percona and the MySQL community in Santa Clara,…
Post: Debugging problems with row based replication
May 6, 2010 By 12 Comments
… Insert a single “seed” row into the table: INSERT INTO repl.t1 VALUES (); Query OK, 1 row affected (0.00 sec) INSERT… Could not execute Update_rows event on table repl.t1; Can’t find record in ‘t1′, Error_code: … know that all the rows are missing, and the one in particular that the server is trying …
Post: Can Innodb Read-Ahead reduce read performance ?
June 26, 2007 By 2 Comments
… queries in queue 12 read views open inside InnoDB Main thread process no. 3956, id 1157658976, state: sleeping Number of rows inserted 60790248, updated… inserted in PK order we have relatively sequential IO and so read-ahead is constantly triggered which makes all thread to wait on single…
