Scala IDE 4.7.1-rc3 very slow recently

[nirav]

I have been using this rc version for several months and have had no issue. But recently after installing some mac updates it have been very slow. 

Here are some symptoms.

1) Eclipse constantly do "updating occurence annotations.."

2) I can see that memory bar in bottom right is constantly moving left and right which indicates tons of garbage collection

3) Slowness triggers usually when I try to do code completion.

I have made no change to eclipse whatsoever. (no new plugins)

Thanks