Re: [ANNOUNCE] Ramback: faster than a speeding bullet

From: david
Date: Wed Mar 19 2008 - 15:36:42 EST


On Tue, 18 Mar 2008, David Newall wrote:

Daniel Phillips wrote:
You will need:

* Two Violin 1010 memory devices

* Four UPS units each rated for one hour at 600 Watts

* Two servers, each with at least two 8x PCI-e slots

* One SAN with a bunch of 15K rpm scsi disks



Honestly, this isn't at all what I understood you to be talking about.
In your very first post you described ramback as "a new virtual device
with the ability to back a ramdisk by a real disk." I assumed "ramdisk"
to mean the Linux psuedo-device. I never understood that you meant an
external device, in fact I thought ramback was *instead of* a Violin.
Since you're talking about external ram, it survives operating system
crashes and of course that is not such a big deal as I was thinking.

I agree. I didn't think ramback was just an advertising mechanism for violin, I thought it was being presented as something that could be used with enterprise hardware like the Sun x4600 (which can hold 256G of ram) and that talk of the violin was just the claim that lots of ram is available so this was a possibility now.

David Lang

P.S. 8xPCI-e slots are only able to do 2GB/s of data transfer, in an earlier post Daniel claimed that you needed 3GB/s of disk to mirror to the disk, so the scenerio listed above looses 1/3 of it's performance compared to what was being claimed earlier.
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