…. If you find that replication is CPU bound, this maybe very helpful. If it is IO bound, then fixing it may not be as easy (or rather, as cheap). Let me explain. If replication is IO bound, most… to fix IO-bound replication is to increase the amount of memory so working set fits in memory. Another – get IO device that…
Post: How multiple disks can benefit for single client workload ?
April 26, 2008 By 4 Comments
… of the people understand IO and as not as I typically use these terms. For me IO is IO bound workload – disks are moving… bound. The beauty of this terminlogy (and so why I use it) – it is very easy to see if system is IO bound or CPU bound, while to understand if MySQL goes through more rows…
Post: Using LoadAvg for Performance Optimization
December 4, 2006 By 5 Comments
… does not really tell you if it is CPU bound load or IO bound load. For example if you have LoadAvg of 10… be light if it is CPU bound – because the system can execute much more CPU bound tasks in parallel or High if… to waiting in the queue. Same true for pure Disk IO bound workload with small difference of disk not being replaceable (if…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
….6 IO bound workload Now let’s see how effective is MRR when the workload is IO bound. For the purpose of benchmarking IO bound workload… These status counters were captured when performing the benchmark on IO bound workload, mentioned above. Counter Name MySQL 5.5 MySQL 5…. Conclusion There is a huge speedup when the workload is IO bound, the query time goes down from ~11min to under a…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 4 Comments
…. IO bound workload Now let’s see how effective are the join optimizations when the workload is IO bound. For the purpose of benchmarking IO bound… workload. BKA makes a huge difference when the workload is IO bound and the query time drops from 2534.41s down to… BKA improves the query time by a huge margin for IO bound workload but does not make much of a difference to…
Post: Why MySQL could be slow with large tables ?
June 9, 2006 By 141 Comments
… even if 50% of rows are accessed, while for disk IO bound accessess we might be better of doing full table scan…. Now if we take the same hard drive for fully IO bound workload it will be able to provide just 100 row… which combine index access with data access, saving you IO for completely disk bound workloads. There are certain optimizations in works which…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… values for any of these variables is indication of IO bound workload. Note however – IO requests submited by threads executing requests are not accounted here so you may have these at zeroes while workload being IO bound still. Next, number of file IO operations is shown as well as computed…
Post: Modeling MySQL Capacity by Measuring Resource Consumptions
March 8, 2011 By 1 Comment
… examines 20 rows, which means about 1 IO per 40 rows… which amounts to pretty IO bound load for me. But average is… less than 1 row in average which makes it very IO bound. So what If I am planning for load growth and… us a good clue how many queries needed no io, needed 1 IO which was not queued (less than 10 ms) or…
Comment: XtraDB benchmarks - 1.5X gain in IO-bound load
December 18, 2008 By 30 Comments
… couple of notes here 1) Even though Vadim called it IO bound benchmark, it is not completely the case. With data just… cares about IO performance but also about contention issues. It would be interesting to see results for completely CPU bound and IO bound benchmarks… a lot of people in reality have. 2) The “emulated” IO workload, by small buffer pool size and innodb_flush_method…
Comment: MySQL on Amazon RDS part 1: insert performance
March 15, 2011 By 37 Comments
… this should not be random IO bound workload. It should be mainly CPU bound. If you want IO bound workload you have to have some… you ad SHA1(id) as a key it would become io bound on insert at some time in the future.
