> I'm looking for price & performance (access time) for: > > 1) Cached RAID
This will be useless for runtime VM or pseudo-VM purposes. RAID cache isolates the application from write burst bottlenecks when syncing disks (e.g. checkpointing transaction logs), but that's about it. For flatter I/O patterns, you'll lose 3-4 orders of magnitude access time over non-cached main memory and it won't be appreciably faster than raw spindle. Wrong tool for the application. > 2) RAM disks Functionally workable, but very expensive. It is much cheaper per GB to buy the biggest RAM chips you can find and put them on the motherboard. The primary advantage is that you can scale it to very large sizes while only losing somewhere around an order of magnitude versus main core if done well. > 3) Internal RAM (using 64 bit architecture?) The best performing, and relatively cheap too. You can slap 32 GB of RAM in an off-the-shelf Opteron system for not much money. The biggest problem is finding motherboards with loads of memory slots and the fact that there is a hard upper bound on how much memory a given system will support. > 4) other Nothing I can think of that will work with Windows. There are other performant and cost-effective options for Linux/Unix systems. A compromise might be to max out system RAM within reason (e.g. using 2GB DIMMs), and then using RAM disks on a fast HBA to get the rest of your capacity. All of this will require a 64-bit OS to be efficient. j. andrew rogers ------- To unsubscribe, change your address, or temporarily deactivate your subscription, please go to http://v2.listbox.com/member/[EMAIL PROTECTED]
