Hi Rich On 08/06/2012 03:26 PM, rtella wrote: We had quite a similiar use case (financial instruments, millions of associated prices in a Gemfire map, need to reason over many (~100'000) instruments, in some cases taking price data (~300mio) into account). We ended up asserting the instruments as facts into WM, do the majority of the reasoning on them, and when really required, accessing the prices from the Gemfire map with a "from" conditional expression For example: WHEN i : Instrument ( assetClass == "Bond" ) ps : PriceSeries ( instrumentId = i.id, priceType = "EndOfDay" ) price : Price ( ) from ps.getPrices() // her we access the Gemfire map ..... So instruments and price series (in our case) are facts in WM, while the prices stay in the Gemfire maps. Of course, that has the drawback that we can not react directly to new or modified prices. Which in our case was ok. Only a minority of the rules needed to take prices into account at all, so we first fired all rules that did not access the maps, retracting all instruments we could. Then the rules with lower salience that accessed the maps fired. -- CU, Joe