… for standalone Innodb, let alone Galera. I had considered a job queue system in Innodb in the past that, in absence of… find which rows that had been “taken” by some other job (that had an open trx and had updated some meta…
Post: Using MySQL as a Queue, and Free Percona Live Tickets
September 15, 2011 By Leave a Comment
… blog: 5 subtle ways you’re using MySQL as a queue, and why it’ll bite you. Go there to read… building a good job queue or batch processing system, and try not to create one inside MySQL. Although the job queue is a great… well in a relational database. However, experience shows me that job queues sneak up in unexpected ways, even if you’re a…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
…_wait: 0.001414 # InnoDB_rec_lock_wait: 0.000000 InnoDB_queue_wait: 0.000000 # InnoDB_pages_distinct: 973 SET timestamp=1325146286… 0 48 6.29 38.53 10.74 1.96 # queue wait 0 0 0 0 0 0 0 # rec lock… log_slow_verbosity and start using pt-query-digest”, your job of identifying queries producing most load will be all the…
Post: Living with backups
November 6, 2008 By 28 Comments
… is out and ready to save someone’s life (or job at least). Unfortunately taking backup does not come free of…, etc.) that can be done with: # cat /sys/block/sd?/queue/scheduler noop anticipatory [deadline] cfq noop anticipatory [deadline] cfq noop… /sys/block/$device/queue/scheduler ] ; then \ echo “cfq” > /sys/block/$device/queue/scheduler ; fi ; done # cat /sys/block/sd?/queue/scheduler noop anticipatory…
Comment: Watch out for your CRON jobs
October 14, 2009 By 19 Comments
… where cron job would periodically fire up 50 instances of php processes (which used mysql as a job queue and a job manager) to do datamining. Prevention of running multiple copies was handled via job_is_running, retry_count etc switches in jobs table and there were surprisingly low…
Post: Using LoadAvg for Performance Optimization
December 4, 2006 By 5 Comments
… no performance problems, for example if you run single batch job on the server with MySQL, Load Average is likely to… increase mainly because of time requests spend waiting in various queues and waiting on locks, the time of true execution may… understand where parallel execution continues and where waiting in the queue starts. If you have fully CPU bound workload which is…
Post: Performance impact of complex queries
January 17, 2007 By 11 Comments
… large data sets(ie some large aggregate queries) and batch jobs. It is not rare to see queries which were taking… the disk, which may be 100% busy running your batch job query. This is especially bad when you only have one… cases I’ve seen average time requests spends in the queue to be over 1 second, which is much more than…
Post: Queries Active vs Transactions Active
September 14, 2009 By Leave a Comment
… STATUS): ————– ROW OPERATIONS ————– 8 queries inside InnoDB, 9 queries in queue 100 read views open inside InnoDB It is relationship between… in the processlist, which often corresponds to some long batch jobs, sometimes you would just see the processlist showing connection is…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… applications have a lot of the same components. Tagging, friends, queues, click tracking, search, paginated displays — we’ve seen these and… what we think is best for you, which is our job). After the kickoff call, we write some notes, and then… that someone else can follow, I am not doing my job. I would also note that the commands I’ll show…
Post: Percona Launches New Support Option for MySQL
October 5, 2010 By 9 Comments
… apple cart a little bit. Oracle is doing a great job improving MySQL, but our customers are telling us they still…. Focusing makes it easier for us to do a good job for you. Why the addition of a focused service on… issues you submitted to us went into one pool, one queue. This works great to keep everyone accountable and connected to…
