Temporarily write-enable buffer to refill it. Access Controls Associate an ACL with each buffer. IOL operations are atomic. File System File cache lives in IO-Lite buffers. No page alignment required.
File system writes allocate new buffers.
Network System Use early demultiplexing to assign ACLs on incoming packets. Cache Replacement and Paging More complex sharing issues than most systems. Cache changes size dynamically. If all data is changed, incremental cost is buffer allocation. If chunks of data are changed, incremental cost is buffer allocation and rechaining.