If I recall correctly,  "data" never officially comes from NVRAM.
That is just logging facilities.

The data comes in and immediately is logged into NVRAM *and* main memory.
The system just does not flush until 10sec or 1/2 full happens.
The blocks stay in main memory until they fall off the most recently used queue.

As long as your requests come in and continuously access the data, it should stay in RAM.

--tmac

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On Thu, Nov 13, 2008 at 12:09 PM, Todd C. Merrill <tmerrill@mathworks.com> wrote:


While I'm thinking of it...  During a conversation with my sales rep.,
this question came up...  (Haven't had a chance to ask our local SE's
yet...)

If a write happens through NVRAM (which it always does), once the
write is acknowledged onto disk and the NVRAM flushed, is that data
in read cache *as well*?  Or, is the path to disk for a write unique,
and when you want to read that data, it has to be read from disk
and *then* put into read cache?

I'm thinking of our software development environment, where we (of
course) do a lot of writing of object files and then linking them into
libraries and executables....

       Until next time...

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