Hits is not proper

Hi All,

I have 4 node cluster set up...Every thing is fine.
I am indexing 5000 document per second ...I trying some real time analytic..I saw strange behavior..hits is not coming proper ...i mean some time it is decreasing also..after some time it is stabilized that time duration is very less.

Any Suggestion or is this bug in ES?

Sumit Gupta