Performance hits with mc.setBlock

I've noticed that my ARM Open-GLES v1 compiled version of Minetest seems to have performance issues when calling mc.setBlock, resulting in noticeable frame drops for a brief moment.
At first I thought this might be due to loading textures into memory, but I don't believe this is the case since there are other nodes in the world that share the same textures and node type. I tried some other examples (LUA code that displays text as blocks or analog clocks that draw hands on a watch face), and they also seems to hitch when blocks are set.
Is this a known issue? Is there something I can try to not cause some jitter and hitching at the moment when mc.setBlock is called?
At first I thought this might be due to loading textures into memory, but I don't believe this is the case since there are other nodes in the world that share the same textures and node type. I tried some other examples (LUA code that displays text as blocks or analog clocks that draw hands on a watch face), and they also seems to hitch when blocks are set.
Is this a known issue? Is there something I can try to not cause some jitter and hitching at the moment when mc.setBlock is called?