May I suggest donloading "Systym Pal" from the App. store? When i experiment with lots of effects, I can see the memory slowly disappear - so I exit wait and re-open & all is cherry. I have the latest IMac w 1 TB Flash, 16 Gigs Ram using Lacie Big 5 (10 TB) thunderbolt (raid 0). Still, i never run any other programs in the background and even unplug my ethernet cable when editing. Been doing that for years. Facebook fans can go cold turkey.
I have been following on the Mavericks forum about the process "com.apple.iconservices". It appears after some boots and not others, it grows & grows & grows. Point is, if one has other issues then the likely place for them to go critical is in Final Cut 6,7 & X. Always been thata way. Always will. I have FCP 10.1.1 loaded to the gills with old projects, old events and & new ones using 2 external drives & internal, all with native 50Mbps Ex-Cam video in (2) 2 hour timelines. Titlles, effects, transitions, mutiple shares with & w/o Compressor. No beach balls. No problems.
Bon ChAmps, amigos