… solution, so we made patch which allows to restrict memory dedicated for data dictionary. Patch was made by request of our customer Vertical… it from InnoDB data dictionary. So there is the trick – if you have big enough table_cache, memory consumed by data dictionary may exceed innodb…
Post: How much memory Innodb Dictionary can take ?
May 6, 2010 By 3 Comments
The amount of memory Innodb will require for its data dictionary depends on amount of tables you have as well as number of fields and indexes. Innodb allocates this memory once… + 0) Threads 408536 (406936 + 1600) Dictionary memory allocated 698012720 So considering about 700M were allocated for dictionary cache in this case we have…
Post: XtraDB: The Top 10 enhancements
August 13, 2009 By 5 Comments
… XtraDB, adaptive checkpointing can smooth out the load, and checkpoint data more aggressively as you approach the end of a log… size (see docs). Data dictionary control – Once an InnoDB table is opened it is never freed from the in-memory data dictionary (which is unlimited…
Post: How much memory can MySQL use in the worst case?
February 12, 2009 By 17 Comments
… minimum, most servers these days need to consider the added memory for InnoDB: specifically, the buffer pool. (There’s also an… enough. Staying with InnoDB, we also need to count the data dictionary. This can take many gigabytes on servers with a lot… keep going! Any stored code (triggers, stored routines, etc) uses memory to execute; so do temporary tables. The following query creates…
Post: How innodb_open_files affects performance
November 18, 2009 By 4 Comments
…. As I mentioned Data Dictionary can take considerable amount of memory – In my case after reading all tables I got “Dictionary memory allocated 392029720″ which means very simple single tables takes about 4KB of space in data dictionary. More complicated tables…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 5 Comments
…memory allocation is Dictionary cache though there could be other reasons too. Memory Leaks There are many kinds of memory…
Post: Connecting orphaned .ibd files
May 13, 2011 By 19 Comments
… the log: InnoDB: Error: tablespace id is 10 in the data dictionary InnoDB: but in file ./sakila/actor.ibd it is 15… refuses to use suggested .ibd file. There is an InnoDB dictionary. It consists of several internal tables. For our topic only… name ‘./sakila/actor.ibd’ already exists in the tablespace InnoDB: memory cache! To refrain from such error ibdconnect does check if…
Post: The Doom of Multiple Storage Engines
May 8, 2010 By 22 Comments
… handle all different cases in Optimizer – such as in memory nature of MEMORY storage engine, clustering by Primary key in Innodb and… can for example get .frm out of sync with internal data dictionary if you crash at wrong time. Transaction Support We have… rid of SQL level table locks and using Innodb internal data dictionary instead of Innodb files. We would use Innodb transactional log…
Post: Percona-XtraDB-9.1: released and new coming features
March 17, 2010 By 14 Comments
… Improved rollback segment scalability Separate purge thread Limited size of data dictionary in memory Increased number of concurrent write transactions (undo slots) ( up… Import / export of buffer_pool Transactional replication Show internal InnoDB data dictionary Show InnoDB locking/io profiling in slow.log I hope…
Post: The perils of InnoDB with Debian and startup scripts
January 28, 2009 By 13 Comments
… lot of tables, InnoDB uses over 3.5G of memory for its data dictionary (the subject for another post — we’re working on… get memory into the buffer pool. Remember we have 3.5G of memory less to play with, solely due to the data dictionary. But… | user | statistics | select … | 6357 | user | statistics | select … | 6358 | user | Sending data | select … | 6359 | user | statistics | select … | 6360 | user | | NULL | 6361 | user…
