The paper proposes models for devolving and redeeming mobile data usage, allowing users to trade data balance efficiently. Analytical and empirical results show how such systems can optimize network resource usage, reduce cost, and increase user flexibility in mobile data plans.
Covers OS performance measurement techniques. Explains performance metrics (throughput, latency, utilization), measurement tools (profilers, benchmarks), workload characterization, bottleneck analysis, and techniques for improving system performance.
Introduces file systems and persistent storage. Covers file abstractions, directories, file operations (open, read, write, close), file descriptors, disk organization with tracks and sectors, and file allocation methods (contiguous, linked, indexed).
Covers memory paging mechanisms for address translation. Explains page tables with page table entries (PTEs), multi-level page tables for space efficiency, translation lookaside buffer (TLB) for caching translations, page faults, and integration with virtual memory swapping.
Presents Remus for high-availability VM replication using asynchronous checkpointing. Covers whole-system replication, speculative execution with buffered output, memory synchronization, disk checkpointing, network buffering, failover mechanism, and performance evaluation.