… run MySQL on. What is important I used Noop IO scheduler, instead of default CFQ. Disclaimer: Please note you may not… remember as Linux kernels 2.6.18+ (which are used on CentOS / RedHat 5.2) are coming with CFQ scheduler as default. So echo ‘noop’ > /sys/block/sda/queue/scheduler should be one of first things…
Post: Heikki Tuuri answers to Innodb questions, Part II
November 4, 2007 By 13 Comments
…-aheads can be waiting in Queue when or Innodb will schedule more read-aheads only when given read-ahead is completed… the amount of system memory. We just deployed a new Linux/Mysql server for a client, upgrading their main database (from… that should be implemented on larger servers? HT: I think Linux often likes to use about 20 % of the available RAM…
Post: Operation Systems do not provide good IO interface for Database Servers
May 11, 2006 By 2 Comments
…. Last time I checked there was IO scheduler with these functions in works for Linux Kernel but I have not seen anything… to happen in background when there are enough resources. IO Scheduler should execute these only if there is bandwidth available so… “Badger” projects at DIKU We tested some protototype patches for Linux kernel and MySQL but we did not get anything ready…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… is already free for grabs but os has not yet scheduled thread so it could proceed with execution. The second piece… query executions are executed by threads running queries. On Unix/Linux you will always see 4 helper threads, on Windows it… is currently active, state of Innodb main thread which controls scheduling of number of system operations – flushing dirty pages, checkpointing, purging…
Comment: Benchmarks of new innodb_flush_neighbor_pages
July 3, 2012 By 8 Comments
… ie. a special algorithm. I think something like the Deadline scheduler would help because it imposes a time limit on I… stalled read/writes. I believe the Deadline scheduler is not the default schedualer of linux but was recommended for ext4. If they…
Comment: Linux schedulers in tpcc like benchmark
October 27, 2009 By 19 Comments
Stumbled on this thread. I’m benchmarking fs/schedulers on a small HW RAID-5 set of 4x400GB SATA. …, Cached, Adaptive Read-ahead. Kernel 2.6.31.5 (Arch Linux). Very short recap with some numbers (40 simultaneous seq reads…+noop: 111MB/s (exploded once with corrupt data when changing scheduler) EXT2+noop: 97MB/s XFS+cfq: 30MB/s Some comments…
Comment: Linux schedulers in tpcc like benchmark
January 30, 2009 By 19 Comments
I have detailed why this happens at http://dammit.lt/2008/02/05/linux-io-schedulers/ – though it all started simply when we compared how I/O behaves on identical machines ( http://dammit.lt/2007/12/13/io-scheduler-deadline-cfq/ )
Comment: Living with backups
November 18, 2008 By 28 Comments
… trick) though I tested various schedulers/setting do see how it affects the results. Originally running Linux-2.6.22, I had…) to slow down to ridiculously low speed! – Using the deadline scheduler (which was the default) gives the best performance in all…
Post: New Keynote Speakers and Sponsors and Applications Open for DotOrg Pavilion for Percona Live MySQL Conference and Expo
January 22, 2013 By Leave a Comment
… Web Services, Google, Clustrix, Scalebase, PalominoDB, Database Trends & Applications, and Linux Journal. We are also now accepting applications for the DotOrg… that we added a fourth day to the 2013 conference schedule. Super Saver pricing ends today, January 22. Confirmed Keynote Presenters…
Post: Percona XtraDB Cluster reference architecture with HaProxy
June 20, 2012 By 63 Comments
… as the operating system, the instructions are similar for any Linux distribution. The client node will have HaProxy installed and it… zlib 1.2.3 120619 13:21:17 InnoDB: Using Linux native AIO 120619 13:21:17 InnoDB: Initializing buffer pool…: ’0.0.0.0′. 120619 13:21:19 [Note] Event Scheduler: Loaded 0 events 120619 13:21:19 [Note] WSREP: Signalling…
