https://kb.juniper.net/InfoCenter/index?page=content&id=KB28129&act=login
Solution:
As already noted, the default behavior for policers is to be programmed per PFE which causes increased actual rates that are above the desired policer rate. Each PFE is programmed with a 5m policer. In this case there two PFEs ( * policer rate = actual traffic rate). The above works out to be (2 PFE * 5mb = 10mb). If a single PFE is used, then the rate would be 5mb ( 1 PFE * 5mb = 5mb). To address this issue, RLI13062 was created for a "shared-bandwidth-policer" knob to be added to the policer configuration. RLI13062 is based off of RLI7995 but added in the fucntionality of DPC cards. RLI13359 was to extend both RLI's to the MPC cards. The "shared-bandwith-policer" carves up the rate of the policer by the amount of PFE's used. In this case (2 PFE / 5mb = 2.5mb/PFE). If a single PFE is used then the rate would be 2.5mb. Less then configured rate