… adds new INFORMATION_SCHEMA table QUERY_RESPONSE_TIME ( full docs are on page response_time_distribution), which looks like time count 0.000001 53 0… commit from our TESTING stage And to demonstrate possible usage of histogram of response time, let me show you how increasing throughput affects response time…
Post: Percona Server 5.5.18-23.0: Now with Group Commit!
December 19, 2011 By 3 Comments
…milestone at Launchpad. New Features Percona Server now supports group commit between XtraDB and the replication binlog. Percona has imported …fixed: #878022 (Laurynas Biveinis) An output buffer truncation check in Response Time Distribution was fixed. Bug fixed: #810272(Laurynas Biveinis) The …
Post: Percona XtraDB Cluster Feature 2: Multi-Master replication
January 19, 2012 By 16 Comments
… on the local node. That is response time of COMMIT consist of several parts: Network roundtrip Certification time Local applying Please note that applying… remote nodes does not affect the response time of COMMIT, as it happens in the background after the response on certification. The two important…
Post: How InnoDB handles REDO logging
February 3, 2011 By 18 Comments
… be useful to explain another important mechanism that affects both response time and throughput – The transaction log. The InnoDB transaction log handles… affect response time? In order to keep ACID compliance, the transaction log must guarantee the logging action happens before the transaction is committed… logged. As the time to log is added to every update it can become an important overhead to your response time. Indeed if…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
… operations. This will have a direct impact in our query response times and throughput. Setting up a cluster using the AMI images…-packet=1M net-buffer-length=16K #we value throughput over response time, get a good plan optimizer-prune-level=0 partition=ON… thread-stack=256K tmp-table-size=64M transaction-isolation=READ-COMMITTED user=mysql wait-timeout=86400 To be continued You can…
Post: Percona Server 5.5.8 Beta Release
February 16, 2011 By 16 Comments
… added. New variable innodb_use_global_flush_log_at_trx_commit was added. Bug fixed: #635399. (Yasufumi Kinoshita) New variable log…: #695906 (Yasufumi Kinoshita) Old variable enable_query_response_time_stats was renamed to query_response_time_stats. (Oleg Tsarev) Existing variable log_slow_verbosity…
Post: Reasons for MySQL Replication Lag
July 29, 2011 By 6 Comments
…, enabling log_slave_updates, setting innodb_flush_log_at_trx_commit=1. Also note there is no such thing as safe… often can see it as higher IO load (IO utilization, response time) while less work is being done in terms of requests… bit different workload and when backup taken at the wrong time may be responsible for unexpected replication lag.
Post: New SpecJAppServer results at MySQL and Sun.
November 12, 2008 By Leave a Comment
… in FDA) [mysqld] sql-mode = IGNORE_SPACE transaction-isolation = READ-COMMITTED max_allowed_packet = 1M max_connections=300 max_connect_errors… was left in tact. Other important settings: transaction-isolation = READ-COMMITTED – this is indeed good setting for many workloads so unless… was done to deal with “dips” which can affect peak response times a lot. The fuzzy checkpointing could be done a lot…
Post: Percona Server 5.1.49-rel12.0
September 15, 2010 By 6 Comments
…warnings is enabled. (Oleg Tsarev) response_time_distribution – Counts queries with very short execution times and groups them by time interval. (Oleg Tsarev) innodb…the MySQL global system variable innodb_flush_log_at_trx_commit. (Yasufumi Kinoshita) innodb_fast_index_creation – Allows disabling of …
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 11 Comments
…_file_path = ibdata1:10M:autoextend innodb_flush_log_at_trx_commit = 2 innodb_flush_method = O_DIRECT innodb_log_buffer_size… was in fact lower number of IO operations and higher response time – so it seems in this case misaligned IO had some… the OS perspective is very similar, due to high concurrency response time in the first case is significantly better. It would be…
