Abstract
Admission control s oftware i s used t o make accept or deny decisions about incoming s ervice requests to avoid overload. Existing media streaming s oftware
includes only limited support f or admission control by allowing for predefined static rules. Such rules limit for example t he number of requests that are allowed to enter the s ystem during a certain time or define thresh-olds concerning the utilization l evel of a single resource such as network bandwidth. In media s treaming appli-cations, however, the bottleneck resource (CPU, Disk I/O, network bandwidth, etc.) might change over time depending on the current demand for different types of audio or video files. This paper proposes a m odel for adaptive admission control i n t he presence of multiple scarce resources. Opportunity costs for a service r equest are determined at the m oment of an incoming r equest and compared to the r evenue of a r equest i n order to make an accept/deny decision. Opportunity costs are based on resource utilization, service r esource require-ments, expected future demand for s ervices, and the r ev-enue per accepted service. The m odel allows rejection of service r equests early to reserve capacity required to perform future service r equests with higher revenues. We describe a number of experiments t o illustrate the benefits of adaptive admission control m odels over static admission control rules.


摘要 接納控制軟件是用來接受或拒絕決定輸入的服務(wù)請求軟件，從而避免過重的負擔?，F(xiàn)有的流媒體只支持有限的軟件，其中就包括接納控制軟件。接納控制軟件使用他們預先定義的靜態(tài)的規(guī)則。這種規(guī)則限制例如靜態(tài)數(shù)據(jù)要求在一定時間內(nèi)都不準進入系統(tǒng)，或定義有關(guān)閾值利用水平的一個單一的資源，如：網(wǎng)絡(luò)帶寬。然而，流媒體應(yīng)用的瓶頸資源(CPU，磁盤I / O，網(wǎng)絡(luò)帶寬等) 依靠目前的需求可能會隨時間改變?yōu)椴煌愋偷囊纛l或視頻文件。本文提出了一種新的模型自適應(yīng)接納控制，在他面前的數(shù)倍稀缺的資源按機會成本來確定服務(wù)請求是當前請求，對照收入請求形成一個接受/拒絕的決定。機會成本是基于資源利用、服務(wù)資源需求預計未來需求與收入接受的服務(wù)。該模型允許拒絕服務(wù)請求過早的備用容量來完成未來服務(wù)請求與更高的收入。我們描述了一系列實驗現(xiàn)象，說明了在靜態(tài)的接納控制模型的自適應(yīng)的接納控制規(guī)則的好處。