Re: high-speed disk I/O is CPU-bound?

From: Rob Landley
Date: Sun May 12 2013 - 12:53:52 EST


On 05/10/2013 09:04:44 AM, David Oostdyk wrote:
Hello,

I have a few relatively high-end systems with hardware RAIDs which are being used for recording systems, and I'm trying to get a better understanding of contiguous write performance.
...
The question is, is it possible that high-speed I/O to these hardware RAIDs could
actually be CPU-bound above ~1400MB/sec?

In some setups your processor is calculating CRCs for the data. It's a fairly cheap operation, but a cheap operation on gigabytes of data can still saturate your memory bus.

Rob--
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