A rather specialist post! A snapshot of our server capacity planning.
Like pretty much everyone else, we have a heavily virtualised server estate. At the minute, we're looking at about 95%+ virtualised.
We have a combination of HP G5, G6, G7, Gen 7 and 8s.
Our on-going strategy is to retire servers that are more than 4+ years old. Better energy efficiency, capacity improvements and increasing support / maintenance costs are our justifications for replacing old kit.
We currently have 12 G5s between 5 and 7 years old and provide 384GB of memory and 12 x 2 x 4 cores = 96 processors (hyperthreading is not active). That makes 32GB per server. These days we're buying servers with 256GB of memory.
So, what are we going to do going forward?
Blades or rack mount?
We're now firmly in the blade server camp at this point - because of the connectivity and management advantages.
Four broad server workload requirements
1) VDI environment - which isn't covered here
2) General server capacity - retiring old HP G5s
3) Specific server capacity for our Tribal SITS Student Information System and data warehouse
- This should free up two existing HP DL580s for general purpose use
4) Test and development
Our Cambridge primary datacentre - Tribal SITS platform
One of our largest projects at the moment is the re-implementation of our student information system. Server performance is probably the least risky aspect of the new SITS implementation. That being said, we're moving from Oracle to SQL Server 2012 and we have no production experience of the workload under SQL Server.
So, we plan to purchase four new servers for our SITS implementation.
We've historically purchased larger DL570 4-way boxes for our database loads - 12 cores per processor @ 2Ghz.
Just for info., the table below outlines the HP Gen 8 vs Gen 9 processor options.
For this new purchase we've elected to go for fewer processors and cores and a higher CPU frequency.
Specifically, the 2 processor Gen 9 BL460c 2 processor, 8 core E5-2667 v3 @ 3.2Ghz. Which should give us a reasonable boost in raw process performance. I know this is a small part of the overall configuration and we're also adding tiered SSD in our HDS HUS150 SAN to provide disk performance. That should theoretically give us 16 processors per server for VMWare - 32 if we go for hyperthreading. This seems ample to support our planned SQL install.
