Would it help to download data locally to speed up backtesting?

[willsims11]

As said in the title, could I download tick data in order to speed up backtests for indicators such as Cumulative Delta?

[bltdavid]

IMHO, the answer is yes,

I never backtest while connected to a data provider.

I always download all the historical data ahead of time,
then I disconnect and start the backtest.

-=o=-

There's another reason.

Friday, after market close, download all the historical data
you need so that you're ready for any backtesting over
the weekend.

That way you don't care about any unscheduled and never
announced server maintenance by your data provider. I
mean, you don't need to connect for anything (you have
all the data), so you're unaffected by any maintenance.

Make sense?

[NinjaTrader_Ray]

NinjaTrader does download historical data on request and caches it locally. The only time it will download data on a backtest is if you are connected and you data request range exceeds the data you have cached locally or you don't have the data at all.