… amount of fsync() activity, it took a total of 14.5 minutes. Not too bad. This is less than my initial test with MySQL… practical applications of all of this? Not much (unless you’re writing complex test cases) but it is clear that loading large amounts of DDL could be a lot faster than it is currently (although loading the data into tables is still going…
Post: Optimizing InnoDB for creating 30,000 tables (and nothing else)
December 22, 2011 By 5 Comments
Post: Shard-Query adds parallelism to queries
November 15, 2010 By 18 Comments
… features a low number of concurrent queries which each examine large amounts of data. Since a single query is single threaded in MySQL, the new optimizations… be CPU bound. What data did I use? I loaded 55GB of the same data used in this earlier post into a partitioned InnoDB table…
Post: Cache Performance Comparison
August 9, 2006 By 74 Comments
…data read from database multiple times. Examining MySQL full query logs from many applications seeing several exactly same queries executed during page load…cache if you have large amount of data in long term cache… ENGINE=MyISAM DEFAULT CHARSET=utf8; INSERT INTO `test` VALUES (‘test’,'MyTestString’);…
Post: How expensive is MySQL Replication for the Master
January 16, 2010 By 13 Comments
… MySQL replication as being quite low overhead on Master, depending on number of Slaves. What kind of load … master performance a lot. I however ran into the case when performance was significantly impacted … threads to send their data to the slave. If you have large amount of slaves the delay from …
Post: Choosing innodb_buffer_pool_size
November 3, 2007 By 39 Comments
…data (total size of Innodb TableSpaces) because it does not only contain data…amount of memory process can allocate so make sure to leave space for other MySQL… you have large amount of tables). I …on the load. Idle …amount of MyISAM, Archive, PBXT, Falcon or other storage engines then you will get into…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…large amount of spin waits and spin rounds significant CPU resources may be wasted. It should come to hundreds of…mysql tables in use 1, locked 0 MySQL thread id 8079, query id 728899 localhost root Sending data…of Innodb load. Not all row operations are created equal of course and accessing of…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 19 Comments
…into account page position in btree index ? HT: No. It is a pure LRU algorithm. PZ: This is one of… on systems with large amount of hard drives. Google… of the checkpointing rate? Postgres exposes this data…load is CPU bound and you’re scaling out you can get better performance by using couple of MySQL…
Post: Quickly finding unused indexes (and estimating their size)
December 5, 2012 By 2 Comments
…loaded them into my schema as separate tables. Then I simply created a view of a UNION DISTINCT of those two tables: mysql…significant enough amount of disk … test data): mysql> select * from droppable_indexes; …mysql> alter table mytable ENGINE=Innodb; However, this blocks and on a large…
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
…load and many things can be happening concurrently. It is very typical to hear complains about MySQL…_time which specifies amount of milliseconds which …important data to be pushed out of buffer…into changing how buffer pool is split into…MySQL has buffer pool which can be easily washed away by large…
Post: Innodb Fuzzy checkpointing woes
May 10, 2006 By Leave a Comment
… most of these are benchmarks)   just after very large amount of pages are…loaded and compare it to constant. However the shared drive at shared MySQL… utilization does not give us enough data – 100% “utiization” corresponds both to 1…real workloads. If you run into what you think is one please…
