May 20, 2013

Testing Samsung SSD SATA 256GB 830 – not all SSD created equal

I personally like PCIe based Flash, but from a pricing point our customers are looking for cheaper alternatives. SATA SSD is an options. There is many products based on MLC technology, and Intel 320 I would say is the most popular. I do not particularly like its write performance – I wrote about it before, [...]

ext4 vs xfs on SSD

As ext4 is a standard de facto filesystem for many modern Linux system, I am getting a lot of question if this is good for SSD, or something else (i.e. xfs) should be used. Traditionally our recommendation is xfs, and it comes to known problem in ext3, where IO gets serialized per i_node in O_DIRECT [...]

Benchmarks of Intel 320 SSD 600GB

I have a chance to test a system with Intel 320 SSD drives (NewRelic provided me with an access to the server), and compare performance with SAS hard drives.

The relationship between Innodb Log checkpointing and dirty Buffer pool pages

This is a time-honored topic, and there’s no shortage of articles on the topic on this blog. I wanted to write a post trying to condense and clarify those posts, as it has taken me a while to really understand this relationship. Some basic facts Most of us know that writing into Innodb updates buffer [...]

Setting up XFS on Hardware RAID — the simple edition

There are about a gazillion FAQs and HOWTOs out there that talk about XFS configuration, RAID IO alignment, and mount point options.  I wanted to try to put some of that information together in a condensed and simplified format that will work for the majority of use cases.  This is not meant to cover every [...]

Ultimate MySQL variable and status reference list

I am constantly referring to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to look up blog posts on variables, or look for content in the Percona documentation or forums. So I present to you what is now my newest Firefox toolbar bookmark: an option and [...]

Effect from innodb log block size 4096 bytes

In my post MySQL 5.5.8 and Percona Server: being adaptive I mentioned that I used innodb-log-block-size=4096 in Percona Server to get better throughput, but later Dimitri in his article MySQL Performance: Analyzing Percona’s TPCC-like Workload on MySQL 5.5 sounded doubt that it really makes sense. Here us quote from his article: “Question: what is a [...]

Virident tachIOn: New player on Flash PCI-E cards market

(Note: The review was done as part of our consulting practice, but is totally independent and fully reflects our opinion) In my talk on MySQL Conference and Expo 2010 “An Overview of Flash Storage for Databases” I mentioned that most likely there are other players coming soon. I actually was not aware about any real [...]

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 [...]