… consistent within the cluster. Also, at the time of this writing, from async stream, MyISAM is not being replicated at all… to the new cluster especially if you are planning to write on multiple nodes. Have PRIMARY KEYS If you still have… affecting async replication like if your workload is CPU or IO bound. Peter wrote some good details about it here. If…
Post: Follow these basics when migrating to Percona XtraDB Cluster for MySQL
May 1, 2013 By 10 Comments
Post: Percona XtraBackup 2.1.0 'release candidate' for MySQL available for download
May 7, 2013 By Leave a Comment
….7 in the 2.0 series at the time of writing). New Features: This version of Percona XtraBackup has implemented full… fixed #1079135. If there are thousands of tables and slow IO then XtraBackup can spend a lot of time opening all…
Comment: Is your MySQL buffer pool warm? Make it sweat!
April 25, 2013 By 6 Comments
… something similar, and I have had a lot of success writing sql queries (taken through Proxy at this stage) to a… impact on the actual DB system, and gets around the IO issues on the server box. may help… may not… Peter…
Post: Is your MySQL buffer pool warm? Make it sweat!
April 16, 2013 By 6 Comments
… duplicate key errors may be faster than an actual database write. The slow logs were split into chunks, each containing roughly…. The y axis is logarithmic, so the difference between the IO usage is 2 orders of magnitude. All graphs looked like…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
… run every fileio benchmark and an IO bound read-write oltp benchmark in autocommit mode. File IO benchmark For the FileIO benchmark, I…_log_files_in_group = 2 innodb_read_io_threads = 8 innodb_write_io_threads = 8 innodb_io_capacity = 200 port = 3306 back_log = 50… that are most relevant to databases – random reads and random writes – IO alignment on a 4-disk RAID10 with standard 64k stripe…
Post: Aligning IO on a hard disk RAID – the Theory
June 9, 2011 By 18 Comments
… you want to align IO to a stripe element as you may otherwise end up reading or writing to more disks than… this is the single IO request from OS, it’s guaranteed to be slower both for reading and writing. So, how do…. The size of logical IO units also is up to the file system. The goal is to write and read as little…
Post: Evaluating IO subsystem performance for MySQL Needs
March 5, 2008 By 23 Comments
… about writes which show us how many cached writes per second we can do – this is important for log writes, which are synchronous IO… 16Kb Number of random requests for random IO: 1000000 Read/Write ratio for combined random IO test: 1.50 Calling fsync() at the… can see all 64 threads are waiting for IO. Now lest see our write test which seems to have some serialization issues…
Post: Virtualization and IO Modes = Extra Complexity
March 21, 2011 By 12 Comments
… 16Kb Number of random requests for random IO: 10000000 Read/Write ratio for combined random IO test: 1.50 Periodic FSYNC enabled, calling… 16Kb Number of random requests for random IO: 10000000 Read/Write ratio for combined random IO test: 1.50 Periodic FSYNC enabled, calling… be sure the system is lying about write completion if we’re using O_DIRECT IO What is my take away on…
Post: Percona Server tree with support of Fusion-io atomic writes and DirectFS
September 24, 2012 By Leave a Comment
… disable “innodb-doublewrite”, retain ACID compliance by using atomic writes, and in IO intensive workloads gain an additional 30-50% in throughput… reduction expected soon. Percona Server 5.5.27 with Fusion-io atomic writes is available from Launchpad repository: lp:~percona-core/percona-server/percona-server-5.5.27-fusion-io-atomic, and the patch…
Post: Operation Systems do not provide good IO interface for Database Servers
May 11, 2006 By 2 Comments
… transactions until they are executed. Most common are syncronous log writes on transaction commits – no other transaction typically can commit until this log write is commited. It also could be used to flush dirty… want to happen in background when there are enough resources. IO Scheduler should execute these only if there is bandwidth available…
