…how many read-ahead requests can be queued at once. Q13: Is there any IO concurrency control – how many random and sequential read aheads can…per flush. That means that under a heavy write load, a new flush and a checkpoint happens more than once per second…
Post: Recovering Innodb table Corruption
July 4, 2008 By 19 Comments
…rows affected (0.03 sec) mysql> insert into test2 select * from test; Query OK, 229376 rows…can find out how many rows do you need to skip exactly to recover as much data as possible. Row size can…
Post: Just do the math!
July 6, 2009 By 4 Comments
…MySQL may execute query above but lest focus on the most typical one – scan the table, when for each row insert (or update) row… can also see how many rows query can process per second in total. Lets assume it is 100K rows per second … numbers you can feed into your model. Using the model we can get …
Post: Implementing efficient counters with MySQL
July 1, 2007 By 16 Comments
…many thousands of updates per second with no problem (assuming log commit would not be bottleneck). Of course the fact you update short rows…inserts go to. The trick you can use here is standard “shadow table” trick – use two tables insert into one and process and truncate another. MySQL…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…per second to start really worry for most CPUs. innodb_sync_spin_loops can…MySQL thread id 9697561, query id 188161264 localhost root update insert into…insert buffer. Next it shows how many inserts were done in insert buffer, how many recs were merged and how many…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…one read-ahead can happen at the same time. How many read-aheads can…per second, then you write 1000 times per second…MySQL bugs opened about multi-core scalability (concurrent queries, autoincrement, concurrent inserts…How does this fit into…
Post: Slow Query Log analyzes tools
September 6, 2006 By 83 Comments
…per second puts more load on server than 10 seconds query running once per second…Rows_sent: 0 Rows_examined: 0 INSERT IGNORE INTO…INSERT/UPDATE ones. Final Note: You do not have to have patched MySQL…
Post: Optimizing InnoDB for creating 30,000 tables (and nothing else)
December 22, 2011 By 5 Comments
… anything near this many tables in the MySQL test suite. So…create 30,000 identical tables, insert a row into each of them and…25 per second. Of course, with the default timeout for a MySQL test (…. Since you could hear how much syncing to disk …than MySQL ever got. With HailDB you can do more than one …
