It depends on the type of chart that you are running and on the number of DataSeries / plots which is used by the indicators on your chart. Let us do an example:
You open a minute chart for ES 06-13 with a 1-minute bar series and a lookback period of 65 days. Then you apply the anaPivotsDailyV41 and the anaCurrentOHLV41 indicators. What is the RAM requirement that you would expect?
Answer: NinjaTrader itself takes about 190 MByte. The lookback period of 65 calendar days corresponds to about 48 working days with 1380 minutes each. The chart bars have five data points, the pivots indicator has 27 plots, the OHL indicator has 12 plots. The values stored are of type double and require 8 bytes each. Therefore the RAM requirement to load that chart should be at least.
48 days x 1380 minutes x (5 + 27 + 12) plots x 8 byte = 23.3 MByte
If you open that chart in NinjaTrader the RAM requirement should rise from 190 MByte to about 213 Mbyte.
If you use high resolution charts built from ticks and add a few more indicators, one chart can easily require 100 MByte or more. It all depends on your chart.
I hope that I made it clear that the RAM requirements mainly depend on the number of bars that you load and the indicators that you apply. It is more or less indepedent from the charting software that you use.
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