How to update curves with data from files?

[lwz]

We working on project related to oil industry. Here is the problem, we have to draw 100 curves in the plot, each curve's sample data is 10,000 points more or less.In our program we read data from file and update curves each time we scroll the plots. Normally, it cost 1 - 10 ms to read data from file and put it into a QPolygonF for one curve. Then it would takes about 1s to update all curves. It's too slow.
Do you have any suggestion?

[Uwe]

In our program we read data from file and update curves each time we scroll the plots. Normally, it cost 1 - 10 ms to read data from file and put it into a QPolygonF for one curve. Then it would takes about 1s to update all curves. It's too slow.
Do you have any suggestion?

Try to use something faster as f.e mmap or better read all data into memory only once.

100 * 10000 * 16 bytes doesn't sound like being a problem for contemporary computer systems - and for your type of application ( have written logging software for oil drilling myself ) you usually don't need 2 doubles for each sample.

Uwe