ExtJs 4 Line chart performance

I have a simple line chart in EXTJS4 with multiple series. The total count of points in lines is about ~5k.

ExtJs 4 chart renders it, but pretty slowly so I'm looking for a way to decrease rendering time. Y axis - numeric, X axis - time. Flash chart from ExtJs3 renders t开发者_开发技巧he same data set much faster.

Any ideas?

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I recommend trying Flot for the charts instead: http://code.google.com/p/flot/