Good afternoon everyone!
We run a number of mission critical databases on a DL460 G6 Blade with P4400 EVA storage. This setup is mirrored across two sites using an application called CA ARCserve Replication. This whole setup is starting to show its age and we are looking at replacement options.
We have our eyes on some HP DL560 G8s (in a similar mirrored setup as above) and have got specs for two E5-4610 processors and 128 GB of memory per server. However, we are a little unsure on storage options. The server itself comes with 5 bays and option for a 25 drive bay external enclose. There are a raft of drive options available, from SSDs, FATA, 7.2/10/15K SAS and so on.
For the on-board storage we need to cater for the following:
- OS (Windows 2008 R2) + SQL server (SQL Server 2005 SP4): maximum of 100 GB
- TempDB: around 50 GB
- Logs: 50 GB
- Pagefile: 128-192 GB
- ARCserve spool drive: .5 – 1 TB
We are currently looking at the following:
- 2*200 GB 6G SSD in RAID 1 for OS plus either TempDB or logs
- 2*200 GB 6G SSD in RAID 1 for pagefile and, if there is room, either TempDB or logs
- 3 * 10k 600 GB SAS in RAID 5 (using the external bay) for spool drive and either TempDB or logs (if still required from SSDs)
Some regarding following this setup:
- With 128 GB, these servers shouldn’t need to do much paging. However, I believe at the very least we need to have a 128 GB pagefile for crash dumps and know that some applications (such as Exchange) still need to page, even on servers with high memory servers. Do we still need to follow the 1.5 ratio for pagefile to physical memory (ie, is 128 GB enough, or will we need 192 GB)? Does the pagefile need to go on SSD? Does having the pagefile on RAID 6 cause issues?
- If for whatever reason we are only able to fit one of TempDB or logs onto the SSDs, which would benefit more from the extra performance, and which would be just as happy on 10K RAID5 SAS?
- Does anyone know enough about ARCserve Replication to know what sort of performance requirements we would need from spool drives? Would they benefit from SSD, or would 10K RAID 6 SAS be enough?
- Is there anything else we have missed or could do differently?
Thanks in advance for any help with this!