unstable ping time

[muhreza]

Dear List.

I have 2 switch 6850 (U24 and 24),connected with 2 link static aggregate ethernet fiber.
One switch (U24) dedicated for Core Switch ,aggregate from many 6200 access switch in many different VLAN,
and the other one is for ServerFarm switch that connect 4 different VLAN server.

The problem is.
If i ping vlan interface and/or server interface in ServerFarm switch from any host within same vlan the ping time result is stable.
but if ping vlan interface and /orserver interface in Serverfarm switch from any host in different vlan (ex: from user access VLAN) the ping time result is unstable.
with "spike" in 10 sequence interval always.

here the configuration (attach)