October 25, 2014

Write performance on Virident tachIOn card

This is crosspost from http://www.percona.com/blog/. Disclaimer: The benchmarks were done as part of our consulting practice, but this post is totally independent and fully reflects our opinion. One of the biggest problems with solid state drives is that write performance may drop significantly with decreasing free space. I wrote about this before (http://www.percona.com/blog/2010/07/17/ssd-free-space-and-write-performance/), using a […]

FlashCache: tpcc workload with FusionIO card as cache

This run is very similar what I had on Intel SSD X25-M card, but now I use FusionIO 80GB SLC card. I chose this card as smallest available card (and therefore cheapest. On Dell.com you can see it for about $3K). There is also FusionIO IO-Xtreme 80GB card, which is however MLC based and it […]

FlashCache: tpcc workload

This is my last post in series on FlashCache testing when the cache is placed on Intel SSD card. This time I am using tpcc-like workload with 1000 Warehouses ( that gives 100GB of data) on Dell PowerEdge R900 with 32GB of RAM, 22GB allocated for buffer pool and I put 70GB on FlashCache partition […]

FlashCache: more benchmarks

Previously I covered simple case with FlashCache, when data fits into cache partitions, now I am trying to test when data is bigger than cache. But before test setup let me address some concern (which I also had). Intel X25-M has a write cache which is not battery backuped, so there is suspect you may […]

FlashCache: first experiments

I wrote about FlashCache there, and since that I run couple benchmarks, to see what performance benefits we can expect. For initial tries I took sysbench oltp tests ( read-only and read-write) and case when data fully fits into L2 cache. I made binaries for FlashCache for CentOS 5.4, kernel 2.6.18-164.15, you can download it […]

RAID vs SSD vs FusionIO

In benchmarks passion (see my two previous posts) I managed to setup all three devices (RAID was on board; Intel X25-E SSD connected to HighPoint controller, FusionIO card) on our working horse Dell PowerEdge R900 (btw, to do that I had to switch from CentOS 5.2 to Ubuntu 8.10, as CentOS was not able to […]

MySQL Replication: ‘Got fatal error 1236′ causes and cures

MySQL replication is a core process for maintaining multiple copies of data – and replication is a very important aspect in database administration. In order to synchronize data between master and slaves you need to make sure that data transfers smoothly, and to do so you need to act promptly regarding replication errors to continue […]

MySQL 101: Monitor Disk I/O with pt-diskstats

Here on the Percona Support team we often ask customers to retrieve disk stats to monitor disk IO and to measure block devices iops and latency. There are a number of tools available to monitor IO on Linux. iostat is one of the popular tools and Percona Toolkit, which is free, contains the pt-diskstats tool […]

Why %util number from iostat is meaningless for MySQL capacity planning

Earlier this month I wrote about vmstat iowait cpu numbers and some of the comments I got were advertising the use of util% as reported by the iostat tool instead. I find this number even more useless for MySQL performance tuning and capacity planning. Now let me start by saying this is a really tricky and deceptive number. Many […]

A closer look at Percona Server 5.6

Yesterday we announced the GA release of Percona Server 5.6, the latest release of our enhanced, drop-in replacement for MySQL. Percona Server 5.6 is the best free MySQL alternative for demanding applications. Our third major release, Percona Server 5.6 offers all the improvements found in MySQL 5.6 Community Edition plus scalability, availability, backup, and security […]