One of the very frequent cases with performance problems with MySQL is what they happen every so often or certain times. … need to know it is not MySQL problem, might be even not problem with your MySQL configuration, queries and hardware, even though…
Comment: Benchmarking single-row insert performance on Amazon EC2
May 16, 2012 By 11 Comments
… one disk seek.) I claim that this schema is not properly indexed. Here’s a theory that seems to explain the performance… 300M or 400M rows, I would expect Inno starts hitting disk. Perhaps you could verify that by watching IOstat. Tim’s….launchpad.net/~mdcallag/mysql-patch/mytools/annotate/head%3A/bench/ibench/iibench.py) is that it measures query performance too, so if…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
… that the disks are 4 5.4K disks in Software RAID5. Also note that the following changes were made on MySQL 5.6… for the best possible performance gain. This is not entirely visible in the manual either for MariaDB or MySQL, but you need to appropriately increase read_rnd_buffer_size/mrr_buffer_size because these have an impact on MRR performance…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…. MySQL Status Counters These status counters were captured when performing the benchmark on IO bound workload, mentioned above. Counter Name MySQL 5.5 MySQL 5.6 MySQL 5.6 w… MariaDB 5.5 w/ mrr_buffer_size=4M Created_tmp_disk_tables 1 1 1 1 1 Created_tmp_tables 1…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… in preparation for the talk comparing the optimizer enhancements in MySQL 5.6 and MariaDB 5.5. We are taking a… optimizer enhancement Index Condition Pushdown (ICP). Its available in both MySQL 5.6 and MariaDB 5.5 Now let’s take…
Comment: How Does Semisynchronous MySQL Replication Work?
March 17, 2012 By 23 Comments
… least one semisynchronous slave, a thread that performs a transaction commit on the master blocks … to its relay log and flushed to disk. ” “Compared to asynchronous replication, semisynchronous replication provides… at least two places” – (cf http://dev.mysql.com/doc/refman/5.5/en/replication-…
Post: MySQL performance on EC2/EBS versus RDS
August 4, 2011 By 10 Comments
… overview of these two approaches to hosting MySQL in the Amazon cloud. In general, MySQL performance overall on EC2 and EBS isn’t… contention. The performance improvements I got with Percona Server were similar to the performance improvements I saw versus stock MySQL 5.1. This… and logical database design influences greatly how much memory and disk resources are required. The application’s access patterns can be…
Post: Getting MySQL Core file on Linux
August 26, 2011 By 1 Comment
… you should consider two things – disk space and restart time. The core file will dump all MySQL Server memory content including buffer… be looking at many times the amount of memory MySQL consumes worth of disk space. You have to do couple of changes… if you expect to do any MySQL profiling or dealing with crashes. It does not slow MySQL performance yet it is very helpful…
Post: MySQL Performance on Memory Appliance
March 31, 2008 By 23 Comments
Recently I have had a chance to check out MySQL Performance on “Memory Appliance” by Violin Memory which can be used … need to do IO to get their data from the disk. With Innodb results were quite poor – I got about 6500… which did not seems to give any significant performance benefit, may be even reducing performance few percents. I also tried running with…
Post: Why you should ignore MySQL's key cache hit ratio
February 28, 2010 By 27 Comments
… randomly positioned, which is a worst-case scenario for spinning disks. This is also very hard to prove, but seems reasonable… that to what your disks are capable of, and draw your own conclusions about whether this is a performance problem. I know… good instrumentation in MySQL to guide your decisions. It is also not the be-all and end-all of MySQL performance, and people…
