… need to know it is not MySQL problem, might be even not problem with your MySQL configuration, queries and hardware, even though… it does not consume too much system resources. Here are some specific techniques to use. Do push concurrency too high Many developers will… even single process overloads system too much in this case throttling by having relatively short queries and introducing “sleeps” between them can be…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…you have reasonable amount of connections but yet MySQL takes much more memory than you would expect, … >> ps.log sleep 60 done Check for Table Cache Related Allocations There are cases when MySQL will … better as you can query temporary tables too: mysql> select sum(data_length+index_length) from …
Post: MySQL for Hosting Providers - how do they manage ?
November 28, 2008 By 15 Comments
… manage to keep things up given MySQL gives you so little ways to really restrict how much resources single user can consume… not take too much combined time in the logs to attract your attention; For example: SET @a1:=repeat(“a”,1000000); select sleep(1…”,1000000); select sleep(1); SET @a12:=repeat(“a”,1000000); select sleep(1); SET @a13:=repeat(“a”,1000000); select sleep(1); … Causes MySQL to “leak…
Post: Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2
May 3, 2011 By 13 Comments
… short sleeps and apparently those sleep delays are too long, so let’s try not sleeping …sleeps is not enough to solve them. However, MySQL 5.6.2 is experimental code and I am sure that next MySQL 5.6 versions will contain a fixed and much…
Post: Understand InnoDB spin waits, win a Percona Live ticket
September 2, 2011 By Leave a Comment
… up and goes to sleep until the mutex is free. I’m simplifying this a lot, perhaps too much, but it’s a… keep checking for a little bit than to go to sleep right away. So, back to the output from SHOW INNODB… has ended. Don’t miss your opportunity to learn about MySQL in London from world-famous experts!
Post: Debugging sleeping connections with MySQL
February 8, 2007 By 28 Comments
… timeouts properly. Or may be you have several connections to MySQL server and right now running query which takes that long… with the process are not only helpful to debug sleeping connections with MySQL but many other cases when you see web application locking up or starting to runs in the tight loop consuming too much…
Post: How to debug long-running transactions in MySQL
March 8, 2011 By 6 Comments
… code so that it can be fixed. I see this much too often, and have developed a favorite technique for tracking down… space (${full}%, ${avail}MB free)”>&2 exit 1 fi host=$(mysql -ss -e ‘SELECT p.HOST FROM information_schema.innodb_lock…/tcpdumps/`date +%s`-tcpdump & mysql -e ‘show innodb status\Gshow full processlist’ > /root/tcpdumps/`date +%s`-innodbstatus pid=$! sleep 30 kill ${pid} fi…
Post: Percona Toolkit 2.0.1 and 1.0.2 released
January 3, 2012 By 5 Comments
… in our plans to create excellent free tools for MySQL administrators. There is one really big thing to talk … size, and set up offsets and modulos and set sleep times and throttle the tool and be careful in… get put into one big chunk that will cause too much load and run it off-hours and restart it …
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
… instances.*EDIT* The storage worker currently logs too much information. This can cause the disk to … data from 1988 to 2010′; mysql> use ontime1; Database changed mysql> show table status like ‘ontime_fact’… innodb-thread-concurrency-timer-based innodb-thread-sleep-delay=0 innodb-use-sys-stats-table…
Post: Performance impact of complex queries
January 17, 2007 By 11 Comments
… your normal working set from OS cache. Operation Systems and MySQL Itself employs various strategies to attempt to minimize such effect… going one after another. Have sleep between them so none of them can take too much resources for too long time. If you delete things do DELETE … LIMIT 1000 and insert sleep 10; in between…
