Tuesday, July 12, 2016

sql server - Configuring SQL for optimal performance... SSD or HDD?



Does anyone know of any comparisons that show how SSDs compare to HDDs for performance in a SQL environment?



I'm trying to understand what type of performance benefit might be gained by moving to SSD.


Answer




If you're doing a large amount of small reads, SSDs are much faster. Here's one of the few comparisons floating around about database performance. Look at the bottom graph for the short answer.



For raw performance, SSDs offer many advantages, the main one being that the seek time is effectively 0, which means all the small HD hits a database does are handled much faster.



There are however some concerns with the current generation on write lifetime, since after so many writes a block isn't usable anymore. They can write quite a bit, I believe the intel's say round a petabyte of bytes for their 32GB drives before they start reaching dangerous levels of ware...this will only get better with time.



For a better understanding of why they perform so much better, read this article from Anandtech on SSDs. He goes into great detail of drives, what's good, what's not, and the ins and outs of how they work. At the top is also a link to a followup articles that covers the latest series of drives.


No comments:

Post a Comment

linux - How to SSH to ec2 instance in VPC private subnet via NAT server

I have created a VPC in aws with a public subnet and a private subnet. The private subnet does not have direct access to external network. S...