According to Cat6500 switch spec, several parameters control the operation of the token bucket:
Rate defines how many tokens are removed at each interval. This effectively sets the policing rate. All traffic below the rate is considered in-profile.
Interval defines how often tokens are removed from the bucket. The interval is fixed at 0.00025 seconds, so tokens are removed from the bucket 4,000 times a second. The interval cannot be changed.
Burst defines the maximum number of tokens that the bucket can hold at any one time. In order to sustain the specified traffic rate, burst should be no less than the rate times the interval. Another consideration is that the maximum-size packet must fit into the bucket.
Any idea if other Cisco switches besides 6500 are also using the same 0.00025 or 1/4000 second interval or different values?