Speed up Cycles Animation Render?

I have a scene with 20,000 identical blocks.

It doesn’t take much to render them but Synchronizing Objects takes 3 minutes per frame. Is there a way for it to stop re-syncing the objects? Just position data changes, not mesh data.
Would linking the blocks fix this?

I figured out a little workaround.

I made all blocks duplicated links. Reduced the sync time but it still syncs. If all blocks were different, I’d have having more trouble. Thankfully they aren’t.