We have 2 VMAX 20K with bi-directional SRDF (A). We have 8 director dedicated for RDF. Per the EMC documenation, a maximum of 64 RDF groups per director can be created. Currently we have a total of 6 RDF groups, and we are looking to quadruple this amount. However, I am concerned that there could be a potential impact to caching on both arrays? Is this a valid concern, if so, what are the factors that would help calculate the max number of RDF groups that could be created per the design of our VMAX. We have 2 engines in each with 64GB of cache on each engine.
Yes, but it's not only depends on the counts of RDF group but it depends how often your source volume new tracks written. That's the reason of cache consuming. I'd like to suggest you looking at current your SRDF/A cache utilization and plan adding more pairs, and try to use DSE pool if necessary. Following KBs for you refer:
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