Eclipse is extremely slow on Fedora 24 -

i running fedora 24 os (with gnome 3) , installed eclipse cdt package fedora repositories (eclipse cdt neon.1), , turned out extremely slow, only when writing code or scrolling, rest of ui works , quickly.

i have done research topic , seemingly problem related gtk backend, , commonly solved running eclipse under gtk2 instead of gtk3. however, has not helped me @ all. options have tried are:

export swt_gtk3=0

and

eclipse --launcher.gtk_version 2 (also tried in eclipse.ini)

these 2 options switch gtk2, noticeable because graphical appearance changes.

i tried older versions of eclipse (juno, kepler , luna) , problem still exists, worse. have increased memory size jvm 3gb , problem remains intact.

the underlying hardware 6 core intel xeon (12 virtual cores hyperthreading) , 32 gb of ram, assume should not represent problem.

i noticed while scrolling or writing, 1 of cores goes 70%-100% utilization, explains lag, don't know how solve.

is there other option can try?