I too am getting serious memory issues with CC 2014 vs CC 2013 doing the exact same tasks. Not sure why, but the default settings for previews, disk cache, and memory seem to give me the best performance. So basically...
- don't enable Disk Cache
- leave the GPU texture memory at 1500MB (Previews -> GPU Information)
- left "RAM reserved for other applications" at 6 GB (in a 32 GB system)
- don't check "Reduce cache size when system is low on memory"
- don't check "Render Multiple Frames Simultaneously"
Win 8.1 64-bit
Six core i7-4930K @ 3.40Ghz
32 GB RAM (DDR3 2133MHz CL9)
Nvidia GeForce GTX 770 4GB
Samsung SSD 840 EVO 250GB (Win 8.1 and installed programs drive)
WD Black 3TB 7200RPM (data drive)
Ahh... that explains a lot then. I almost always scrub audio in After Effects.