use mongod store small values , average size is 80 bytes,
chunk size is 64MB.
when add new shard into cluster, moveChunk start, and always say chunk is too large,
can't move, then split the chunk with force:true option.
limiting split vector to 250000 (from 634775618) objects
634775618 seems to large! it is half of the collection objects count.
i found in source code ,
when force is true, it will set maxChunkSize to the chunk size.
but i think dataSize is the size of whole collection , not the chunk,
so when force is true, it will always split at 250000 pos, not at 1/2 of the chunk.
am i wrong ?