DivX playback stutters even on high-end devices

I'm attempting to watch a standard def DivX-in-ogm file on a Pixel C and I'm getting lag or frame drops even with the performance settings maxed. Is VLC not setting a high enough CPU priority or something? I'm pretty sure my old 900MHz Celeron was able to decode DivX in real time without causing problems to the rest of the OS on the same CPU, and modern multicore Android devices should be a lot faster.