… step is such that the hash table fits in memory. You can read more about the hash join algorithm here. Now let…_size and both of these buffers should be increased appropriately for the best possible performance gain. This is not entirely visible in… need to appropriately increase read_rnd_buffer_size/mrr_buffer_size because these have an impact on MRR performance, and BKA uses…
Post: Multi Range Read (MRR) in MySQL 5.6 and MariaDB 5.5
March 21, 2012 By 10 Comments
…lookup. Thereby, converting Random access to one or more sequential access. There is one another interesting thing…, there is a slight increase in query time for MySQL 5.6, increase of 0.02s. But the…buffer. But there is no performance improvement when the workload is in-memory, in fact MRR adds extra…
Post: Should I buy a Fast SSD or more memory?
April 8, 2010 By 10 Comments
… buffer pool of between 2G and 22G (to test performance compared to memory fit). Hardware was our Dell 900 (specs here). To… pool (best performance). It’s important to point out that once you hit this point, a further increase in memory at all. The… To get the same improvement with memory, you would have needed to add 60% more memory -or- 260% more memory for a 5x improvement.Â…
Post: Is there benefit from having more memory ?
November 19, 2010 By 10 Comments
…-or-more-memory/, caused quite interest, especially on topic SSD vs Memory. That time I used fairy small dataset, so it caused more questions… of memory? If we use fast solid state drive, should we still be looking to increase memory, or that configuration provides best possible performance…
Post: MySQL-Memcached or NOSQL Tokyo Tyrant - part 1
October 15, 2009 By 16 Comments
… increasing data size? Here is where people start to scratch their heads. They naturally assume they need to scale more, we need more memory! If performance sucks, we must need more. So here comes the bigger boxes…
Post: Predicting Performance improvements from memory increase
August 7, 2008 By 6 Comments
… I guess is how much should I see performance improved in case I increase memory say from 16GB to 32GB. The benefit indeed… not expect to gain much by increasing the memory. This however have to be watched carefully. Performance does not always stays the same… with same cache hit ratio more data and more load means there are higher demands for IO subsystem performance. By far the best…
Post: When is it a time to upgrade memory ?
September 16, 2008 By 11 Comments
…load is getting more IO bound or may be just because amount of queries increased dramatically or … and see how performance depends on buffer size so you get and understanding what Memory-To-Disk …you can use it as guidance to add more memory or more servers. Of course this is all oversimplifications -…
Post: MySQL Server Memory Usage
May 17, 2006 By 18 Comments
… some more space can add up. Running small queries might only barely increase memory consumption for given thread, however if table will perform complex… you may find out increasing sort_buffer_size from 1MB to 4MB and 1000 max_connections increases peak memory consumption just 30MB not…
Post: Heikki Tuuri Innodb answers - Part I
October 26, 2007 By 17 Comments
… Q17: How InnoBD handles blobs/text fields (needs more info) According to the documentation, InnoDB put …patch that makes InnoDB’s flushes smoother and increase performance substantially. I assume there is lots of …buying 40 8-core boxes with 32G of memory. Have any specific thoughts here? INNODB was …
Post: InnoDB Flushing: a lot of memory and slow disk
March 31, 2011 By 57 Comments
…, estimate, keep_average). Why do we need one more? Okay, first let me start by showing the…minutes). This comes from the fact that MySQL performs changes in memory at a faster rate than it can…MySQL’s general recommendation for this case is to increase innodb_io_capacity and decrease innodb_max_dirty…
