why LVS-DR rr mode not average?

["lijixin" <lijixin@xxxxxxxxxxxxx>]

Dear all:
I use LVS-DR rr mode,two same windows as realserver,at first,the request of 
distribution to every realserver seems average,but after 3-4hours later,the 
request of distribution is not average,it always to the same machine till this 
machine no responses.why??
as follows:

First running situation: 

IP Virtual Server version 1.0.9 (size=65536)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.1.214:http rr
  -> 192.168.1.115:http           Route   1      2          495
  -> 192.168.1.116:http           Route   1      3          493


3 hours after running situation:

IP Virtual Server version 1.0.9 (size=65536)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.1.214:http rr
  -> 192.168.1.116:http           Route   1      1          410       
  -> 192.168.1.223:http           Route   1      85         177       

who could tell me why??
thanks a lot!!

Best Reards!!
lijixin