MySQL has multiple mutex implementations viz. wrapper over pthread, futex based, Spin-Lock based (EventMutex). All of them have their own pros and cons but since long MySQL defaulted to EventMutex as it has been found to be optimal for MySQL use-cases.
“Running MySQL on selected NUMA node(s)” looks pretty straightforward but unfortunately it isn’t. Recently, I was faced with a situation that demanded running MySQL on 2 (out of 4) NUMA nodes.
Managing global counters in a multi-threaded system has always been challenging. They pose serious scalability challenges. Introduction of NUMA just increased the complexity. Fortunately multiple options have been discovered with hardware lending support to help solve/ease some of these issues. In this blog we will go over how we can make Global Counter NUMA SMART and also see what performance impact each of this approach has.
ARM community that has developers from varied organizations has contributed some really good patches to MySQL. Most of them are awaiting acceptance. Blog is meant to analyze these patches along with their pros and cons. Hopefully this would help ease MySQL/Oracle to accept these long-awaited patches.
Often we observe jitter in MySQL throughput while running benchmark. Same could be true even for users but there are so many other things to look for (especially IO bottleneck) that the aspect we plan to discuss today may get overlooked. In this article we will discuss one such reason that could affect the MySQL performance.
InnoDB uses mutexes for exclusive access and rw-locks for the shared access of the resources. rw-locks are used to control access to the common shared resources like buffer pool pages, tablespaces, adaptive search systems, data-dictionary, informaton_schema, etc… In short, rw-locks play a very important role in the InnoDB system and so tracking and monitoring them is important too.
By and large this would be a topic of interest for most of us including me when I started to explore this space. Before we dwell into the numbers let’s first understand some basic differences between 2 architectures. Beyond being CISC and RISC let’s look at the important differences from MySQL perspective.
I am sure most of you may have this question. In fact, I too had it before I started working on #mysqlonarm initiative. What does it take to run MySQL on ARM? Does it really work? What about dependencies? What kind of performance does it have? What about support? Is there enough community support? This could go on…..
ARM processors are everywhere. It is quite likely some of you may be reading this blog from an ARM powered device. Phone, IoT devices, consumer and home appliances, health-care devices, all are powered by ARM processors. ARM processors are known to be power efficient and so most of these devices that demands a long recharge cycle but less processing power started using them.