…=52428800 read_buffer_size=131072 max_used_connections=13 max_threads=2002 thread_count=6 connection_count=6 It is possible that… messages after this, something went terribly wrong… stack_bottom = 7f9244a8fdb8 thread_stack 0×40000 /usr/sbin/mysqld(my_print_stacktrace+0×35)[0x7d0765…. Query (0): is an invalid pointer Connection ID (thread ID): 3 Status: NOT_KILLED You may download the Percona Server operations manual…
Post: trx descriptors: MySQL performance improvements in Percona Server 5.5.30-30.2
April 12, 2013 By 3 Comments
… of the trx_list scan in MySQL 5.5 basically kills throughput on high concurrency. The picture changes dramatically when the…. there’s a notable drop in throughput starting from 256 threads. But Percona Server’s scalability is the same as in…
Comment: The perils of InnoDB with Debian and startup scripts
January 28, 2009 By 13 Comments
I have also used the “KILL 7″ approach in the past and found that another thread is often opened up immediately with a “CHECK TABLE” on the next table in the database. I needed to keep killing threads until it gets to the end. [Ubuntu 8.04 Hardy]
Post: MySQL Partitioning - can save you or kill you
December 11, 2010 By 45 Comments
… in buffer pool completely so replication became CPU bound (single thread) instead of IO bound. You could celebrate but hey…. you… by UUID from 400 to 20 per second (from single thread). Decreasing number of partitions made replication less efficient but the…
Post: How to find MySQL queries worth optimizing ?
September 11, 2012 By 6 Comments
…:44 # User@Host: root[root] @ localhost [] # Thread_id: 64914 Schema: sbtest Last_errno: 0 Killed: 0 # Query_time: 9.031233 Lock_time…:05 # User@Host: root[root] @ localhost [] # Thread_id: 65005 Schema: sbtest Last_errno: 0 Killed: 0 # Query_time: 0.000323 Lock_time…:22 # User@Host: root[root] @ localhost [] # Thread_id: 65098 Schema: sbtest Last_errno: 0 Killed: 0 # Query_time: 0.000234 Lock_time…
Comment: How much memory can MySQL use in the worst case?
January 21, 2012 By 17 Comments
While this thread is quite old. The problem of figuring these things out … OOM killer killing a suddenly growing mysqld would go away. The counterpoint to that of course is that the threads running inside… “deadlock” condition were detected which would kill a thread a free up memory, allowing other threads to continue. Having suddenly bumped into this…
Post: Can MySQL temporary tables be made safe for statement-based replication?
May 26, 2008 By 8 Comments
… the bottom of the matter. First, I stopped the slave threads so I could choose which statements to replay on the…’s let the slave replay events up until position 207, kill it, and restart it: slave1 > show slave status\G *************************** 1. row… it is. There’s one more angle to the email thread that inspired this article: what if the whole transaction is…
Post: Living with backups
November 6, 2008 By 28 Comments
… && $was_running == 0) { kill 18, $pid; $was_running= 1; } … my $sth= $dbh->prepare(‘SHOW GLOBAL STATUS LIKE “Threads_connected”‘); … if… status every second and in case the number of connected threads goes above 50, it sends STOP signal to the archiving process. Whenever the number of connected threads drops down back to 9 or less, the script sends…
Post: Choosing innodb_buffer_pool_size
November 3, 2007 By 39 Comments
… include MySQL buffers – query cache, key_buffer, mysql threads, temporary tables, per thread sort buffer which can be allocated. There are also… have memory usage spike you may have MySQL Server being killed by OS instead of temporary swapping few things out. Two… be in swap rather than memory you will have another threads piling up waiting on the same lock till IO completion…
Post: Ultimate MySQL variable and status reference list
January 8, 2011 By 4 Comments
….commanual thread_cache_sizeblogpercona.commanual thread_concurrencyblogpercona.commanual thread_handlingblogpercona.commanual thread_stackblogpercona.commanual Threads_cachedblogpercona.commanual Threads_connectedblogpercona.commanual Threads_createdblogpercona.commanual Threads_runningblogpercona…
