I was referring more to THIS:
Basically, the indexing service keeps track of all the media files you have, and tries to keep cached file handles for them in its memory. Since the MyCloud has rather limited memory and does not have the zram swap module baked in (Really, WD— WHY did you do that!?) the device starts having to hit the swap partition pretty hard as the index size grows beyond a certain point-- at least that is the theory.
Since the internal sata disk is the physical device hosting the swap partition, its read and write accesses will be in contention with this disk swapping, which could be the source of your stuttering, and also neatly explain why USB connected disks being shared by the MyCloud are inimpacted. (No swap partitions on those, no I/O contention.)
Was asking about SSH access, because we could get a reading from [free], [top], and [cat /proc/swaps] to see if large amounts of swap are allocated, and by what process.
