@jsulm I had the graph over an hour and the memory did not increase but the program started to slow down.

I think I just figured it out by setting using a bool and setting it to false at the beginning. Then just before attaching the axis determine axis visibility. If the bool is false, set the axis visibility to true then set the bool to true. The next time thru, the bool will be true and set visibility to false. I ge both lines and only one set of scales.

if (axisXHasBeenAdded == false)
{
axisX->setVisible(true);
axisXHasBeenAdded = true;
}
else
{
axisX->setVisible(false);
}

When using line series, we've had severe performance problems. We end up with thousands of series to handle all of the gaps and have to create parallel scatter series because we want icons for each point that aren't part of the standard icon set.

We pay a huge cost both constructing and destructing the series. Seems like it may be refreshing on each add series, but even removeAllSeries is slow. Have tried many things to suspend the painting, but with no timing effect.

Any ideas on how to have many gaps without destroying performance?

great! That works. With that I can spare the toggle functions at all.
Thanks!