The design and evaluation of policy-controllable buffer cache

Traditional software using BBA(Black Box Abstraction) paradigm may show performance degradations under unpredicted situations. OI(Open Implementation) is proposed to solve the problem of BBA. While conserving the advantages of the BBA, the OI provides clients with interfaces to control the strategy of the black box, and thus makes the black box to be flexible and reusable in various situations and requests. In this paper we attempt to solve the problem of the buffer cache in the operating systems using the OI. We propose a buffer cache design which can support multiple buffer replacement policy. The buffer replacement policy can be controlled by client using provided meta-interface. We modify the kernel of Linux to get performance data. According to our experimental results on Linux, the performance is improved up to 36 %. We conclude that the OI can be an alternative to BBA.