…Sending data | 0.162272 | | end | 0.000008 | | query end | 0.000004 | | closing tables | 0.000032 | | freeing items | 0.000035 | | logging slow…
Post: Implications of Metadata Locking Changes in MySQL 5.5
February 1, 2013 By 9 Comments
….6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the Metadata….000002 | | Sending data | 0.000040 | | end | 0.000003 | | query end | 0.000002 | | closing tables | 0.000003 | | freeing items | 0.000007 | | logging slow query….000004 | | Sending data | 0.000033 | | end | 0.000003 | | query end | 0.000002 | | closing tables | 0.000004 | | freeing items | 0.000009 | | logging slow query…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… over decent period of time. In the very start of printout Innodb will print: ===================================== 060717 … be free already. OS Waits are relatively slow, and if you get tens of thousands …thread id 8079, query id 728899 localhost root Sending data select sql_calc_found_rows * from b …
Post: Living with backups
November 6, 2008 By 28 Comments
… when a task is reading a lot of data very quickly, just as the archiving process does when…filled with random information additional I/O occur slowing everything down even further. What does it all …number of connected threads goes above 50, it sends STOP signal to the archiving process. Whenever the…
Post: MySQL 5.6 vs MySQL 5.5 and the Star Schema Benchmark
March 11, 2013 By 7 Comments
…data) and I also testing a 4G buffer pool, which is larger than the data. Very…data and the IO is slow (when the FS cache is cold, IO to slow… | 12 | Sending data | 33….
Post: How to use tcpdump on very busy hosts
April 18, 2011 By 17 Comments
…with tcpdump on “very” busy hosts. You might be thinking, “very busy is a… a situation where a single connection sends two queries and gets two responses,…confusion about which queries are really slow. Recently, I got more than 60%…Â Â # duration to capture tcpdump data in seconds (1200 = 20 min) TMP…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… compare it against the server’s variables or whatever other data I need, and write something instructional to the client about…. It is very customer-specific, and we work with what we have. Sending the report to the client After the slow query log analysis is done, I format all my analysis for sending, add…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… just for new connections as in MySQL. This is very helpful for measurement as otherwise we might not … auto_inc; Compare that to Percona Server with log_slow_verbosity=full: # Time: 111229 3:11:26 # User@Host…95% of the times and is sending 202 rows and 83.83k of data per query while its also …
Post: How to find MySQL queries worth optimizing ?
September 11, 2012 By 6 Comments
…they end up sending. In this case if I index the table I get the following record in the slow query …to two tables. In case of “real” access to the data it will: # Time: 120911 17:28:12 # User@Host: …B/A is 10x or more this query is a very serious candidate for optimization. This is simple method and …
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 5 Comments
… and observing whenever memory usage shrinks can be very helpful in diagnostics. If you have many applications…allocated on server and Com_stmt_send_long_data to see whenever sending long data feature is used as it…to detect memory leaks like valgrind are too slow to run in production. So the best …
