…high margin in the price) as well as high performance in general and stable performance under high…space reservation to get sustainable write performance (Tuning Techniques for Writes). I took FusionIO ioDrive… and it can be quite important in workloads like FlashCache, where card have both concurrent…
Post: How Innodb Contention may manifest itself
July 28, 2011 By 1 Comment
… of CPU being idle, increased compared to normal workload portion of system CPU and high number of context switches. These correspond to… switches being done, which well may be normal – if your workload has large portion of it being “critical section” where only… spin locks loops is something i would consider last resort tuning, the performance improvements it provides is typically rather limited and…
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…with systems that are at any level of tuning, from completely untuned to a system that’…as monitoring, alerting, backups, caching, reverse proxies, and high availability solutions, all of which we can … and can completely change the performance profile and workload of a server, so it’s often worth…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 28 Comments
…:100″ or “your key cache hit ratio should be very high, ideally above 99.9%” or “if your key cache hit… heavy query workloads. Both have a key_buffer_size of 4GB. Now can you tell which server is badly tuned? — No, you… tell you that both servers are identically tuned, and they have identical data, hardware, and workload. Even that doesn’t help, though…
Post: Economics of Performance Optimization
March 13, 2008 By 9 Comments
… the market, especially if you consider some workloads may have problems with latency rather than … moving the application. On reasonably tuned applications when further tunings are expensive you may well upgrade… fast rolling out new stuff especially in high pace markets. Besides lack of resources it…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… the query execution plan, is not sufficiently tuned and it is recommended to turn this off…workload Now let’s see how effective is MRR when the workload is IO bound. For the purpose of benchmarking IO bound workload… MariaDB and MySQL 5.6 are reporting high numbers for Innodb_rows_read, which is …
Comment: MySQL 5.5 and MySQL 5.6 default variable values differences
February 21, 2013 By 8 Comments
… OLTP workloads they have. back_log is calculated based on max_connections. You’re right that higher values are desirable at high…. max_connections was the best proxy we had for expected high connection rates when dynamically configuring it at startup. join_buffer…’s helpful for a workload to have qc on. QC off tends to be best for well tuned OLTP and web sites…
Post: Is MySQL 5.6 slower than MySQL 5.5?
February 18, 2013 By 23 Comments
… such simple workload ? How much of this slowness comes from Performance Schema ? Whenever we get difference higher or lower with high concurrency… over 25% is rather substantial and if fair amount of workloads will see similar kind of overhead I expect a lot… phase should not increase with contention. Granted I have not tuned MySQL 5.6 for best performance going with defaults outside…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… fsync() for modified files. Constant high values for any of these variables is indication of IO bound workload. Note however – IO requests… is smaller than allocated buffer pool size so you can tune it down. Even if free pages is zero as in… – it is very workload dependent. Sometimes 950/1000 will be enough, sometimes you can see IO bound workload with hit rate of…
Post: MySQL performance: Impact of memory allocators (Part 2)
March 8, 2013 By 12 Comments
… id=N. Test workload with this query allows to generate significant load and check server behavior under very high pressure Observations: 4… the query processing. I believe that both allocators can be tuned to handle such cases better – for instance allocate more arenas… page purging may have some correlation with decreasing performance in workloads with MySQL. # Test: POINT_SELECT:throughput, QPS # # Set 1 – 5…
