Why mysql cluster requires more ram as compared to basic mysql db setup (no cluster)?
What is the ideal ram requirement for a mysql cluster with 2 mysql servers on 2 different hosts ?
One of the strengths of MySQL Cluster is that it can be run on commodity hardware and has no unusual requirements in this regard, other than for large amounts of RAM, due to the fact that all live data storage is done in memory.
I have no direct experience related to MySQL cluster, but I believe it's due to data caching (aggresively). Theoritically, by caching you anticipate locality pattern i.e one tends to access certain subset of data over and over again, so it makes sense to cache it in local node.
So how much? I believe there's no real threshold. Ram it as much as you can... 2 or 4 Gigs I guess is the reasonable amount..or more if you have bigger data set.
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