…seems that InnoDB performs better when a larger number of rows …raw performance, but there are limitations which MyISAM imposes that are…innodb_buffer_pool_size=64G innodb_log_file_size=4G innodb_file_per_table innodb_stats_on_metadata=off innodb_file_format=barracuda innodb_log_buffer_size=32M innodb…
Post: More on MySQL transaction descriptors optimization
April 26, 2013 By Leave a Comment
… was using 8 tables with 1M rows each (about 2.1GB) for his … of transactions, its applicability is quite limited. Namely, it requires the list of…innodb_log_buffer_size = 16M innodb_buffer_pool_size = 52G innodb_log_file_size = 2000M innodb_log_files_in_group = 2 innodb_file_per_table = true innodb…
Post: Innodb row size limitation
April 7, 2011 By 12 Comments
… ~8000 bytes limit on row size (8126 as reported by my test installation). This limit is a consequence of InnoDB storing two rows on a page… store a single row on a page. If your row has variable length columns and the complete row size exceeds this limit, InnoDB chooses variable length…
Post: How innodb_open_files affects performance
November 18, 2009 By 4 Comments
… control its size and it can take significant amount of memory in some edge cases. Percona patches though provide innodb_dict_size_limit to… the row in each of 100K tables. This test ran about 180sec first time and about 260sec second time (with innodb_flush… innodb_open_files=16384 I got about same crash recovery speed though with no warnings. So it looks like innodb_open_files_limit…
Post: Optimizing InnoDB for creating 30,000 tables (and nothing else)
December 22, 2011 By 5 Comments
…, in fleshing out the test cases for this and innodb_dict_size_limit I was left with the not so awesome task of… language that will create 30,000 identical tables, insert a row into each of them and then drop them. Establishing the… initial size. This also did not help. So how fast is InnoDB under all of this? Am I hitting a fundamental limitation in InnoDB…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… Innodb kernel and still has 400 tickets to use. Innodb tries to limit thread concurrency allowing only innodb_thread_concurrency threads to run inside Innodb… index Innodb builds for some pages to speed up row lookup replacing btree search with hash search. This section shows hash table size…
Post: Fishing with dynamite, brought to you by the randgen and dbqp
November 16, 2011 By Leave a Comment
… crashes after setting innodb_dict_size The basics of this were that the server was crashing under load when innodb_dict_size_limit was set… value in the ‘rows‘ section tells the data generator to produce 50 tables, with sizes from 1 row to 50 rows. 3) Specify the… test_bug758788(self): test_cmd = (“./gentest.pl ” “–gendata=conf/percona/innodb_dict_size_limit.zz ” “–grammar=conf/percona/translog_concurrent1.yy ” “–queries=1000…
Post: Recovering Innodb table Corruption
July 4, 2008 By 22 Comments
…Innodb tablespace got corrupted. In such cases Innodb will typically print something like this: InnoDB: Database page corruption on disk or a failed InnoDB…test limit 200; Query OK, 100 rows affected…Row size can be good help to you. In this case we have about 280 bytes per row so we get about 50 rows…
Post: Reasons for run-away main Innodb Tablespace
June 10, 2010 By 2 Comments
…Innodb Tablespace. Insert Buffer size is also restricted to half of the buffer pool size (can be changed via innodb_ibuf_max_size… row and so be responsible for one undo entry or it may modify millions of rows. Row size…accommodated in the database. It is not limited to undo slots. When we’re speaking…
Post: Blob Storage in Innodb
February 9, 2010 By 13 Comments
… it. How blobs are stored in Innodb ? This depends on 3 factors. Blob size; Full row size and Innodb row format. But before we look into… whole row onto Innodb page. At least 2 rows have to fit to each page plus some page data, which makes the limit about… you’re interested to learn more about Innodb row format check out this page in Innodb docs: It is worth to note I…
