… random write asynchronous 8 threads IO, the test is done just after a secure erase operation on the card. The card… the question is how much MySQL can use. In his keynote Mark Callaghan mentioned that Fusion-io cards they use are highly underutilized. With the performance variance we see it is a good question how does it affect…
Comment: ext4 vs xfs on SSD
April 25, 2012 By 23 Comments
… you think I should use to recommend that or another product/filesystem? For me – amount of bugs (how stable it is) is… are most interested in recommendation that they can use today, now in production deployment. How stable will be product is 2 years… months. Following your logic, it seems I just should go ahead and recommend to use btrfs to everyone, because it has so…
Comment: ext4 vs xfs on SSD
May 3, 2012 By 23 Comments
… ext4, and how much of their recommendation comes from the days of ext2/ext3. So I decided to use sysbench and plot…, setting the correct sunit/swidth for the RAID array, or using nobarrier, all have no statistically significant impact on performance, which… issue that Dave was referring to above. Disclaimer: I’m just someone who runs their own benchmarks, and am not religious…
Comment: How to calculate a good InnoDB log file size
May 1, 2012 By 33 Comments
Hi! I come from Viet Nam. Now i want to check capacity (free space & used space) of datafile on InnoDB (MySQL). How to command? I just research for MySQL, hope you help me. Big thanks!
Post: How FLUSH TABLES WITH READ LOCK works with Innodb Tables
March 23, 2012 By 20 Comments
… to complete. Here is example how it can look: mysql> show processlist; +——-+——+———–+———-+———+——+————————-+—————————–+———–+—————+———–+ | Id | …way or another. If you’re just using Innodb tables and you’re not…
Post: How We Got Here
April 9, 2012 By 6 Comments
… equal footing. The event balances community, business, and technology, not just open source. Many key decisions were even made outside of… none. Attendees will hear from people who use MySQL in production systems and know how to operate it and develop against it… are the people who are uniquely qualified to talk about how MySQL works in practice. Sponsors will have an engaged and…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
… MariaDB 5.5. Handler_mrr_rowid_refills counts how many times the buffer used by MRR had to be reinitialized, because the… adds extra sorting overhead which means that the queries are just a bit slower as compared to MySQL 5.5 MRR…_aheads. Another thing to take away is that MariaDB is just a bit slower as compared to MySQL 5.6, may…
Post: Index Condition Pushdown in MySQL 5.6 and MariaDB 5.5 and its performance impact
March 12, 2012 By 12 Comments
… the part on which range condition is applied cannot be used for filtering records. For example, suppose you have a key…
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 3 Comments
…. There is no comparable variables of how many user variables are allocated (and how much memory they use). Memory Tables MEMORY tables can… Server again which provides a lot more insight about how memory is used. I would note though the output is a bit…, it should be just swapped out and when never needed again. So if you see swap file used space gradually growing and…
Post: Join Optimizations in MySQL 5.6 and MariaDB 5.5
April 4, 2012 By 2 Comments
…_orderdate LIMIT 10; In-memory workload Now let’s see how effective are the join optimizations when the workload fits entirely… ~10s. Another thing that is important to know is that, just increasing the join_buffer_size is not going to provide… size of the buffer that MRR uses appropriately. In my tests I noticed that with just the join_buffer_size increased to…
