We have Dell servers running Windows with Perc 5/E, 6/i, 6/iR, etc. controllers. Each controller has 256MB of cache and a battery, so I turned on Write Back on the controller and turned off caching on the physical disks, for performance and data safety respectively. However, I am unsure of what to set the Read Ahead settings to for these workloads. I'm leaning towards Adaptive Read-Ahead for everything, because we don't really have any specialized or intense workloads. Let's say I have a...
2x 250GB SATA disks in RAID-1 with a stripe size of 64KB
- runs a file server for ~15 users, print server with ~5 printers, DHCP, DNS, and that's about it
Also, let's say I have a...
14x 750GB SATA disks in RAID-6 w/64KB stripe
- big DAS unit for backups
Finally, let's say I have a...
6x 450GB SAS disks in RAID-10 w/64KB stripe
- running various VMs (WSUS, file server for 25+ users with some large media files that also replicates off-site, email archiving, Sharepoint, and many more!)
What Read Ahead setting would be suited to these?