Anonymous RPC: Low-Latency Protection in a 64-Bit Address Space

In this paper, we propose a method of reducing the latency of cross-domain remote procedure call (RPC). Traditional systems use separate address spaces to provide memory protection between separate processes, but even with a highly optimized RPC system, the cost of switching between address spaces can make cross-domain RPC's prohibitively expensive. Our approach is to use anonymity instead of hardware page tables for protection. Logically independent memory segments are placed at random locations in the same address space and protection domain. With 64-bit virtual addresses, it is unlikely that a process will be able to locate any other segment by accidental or malicious memory probes; it impossible to corrupt a segment without knowing its location. The beneet is that a cross-domain RPC need not involve a hardware context switch. Measurements of our prototype implementation show that a round-trip null RPC takes only 7.7s on an Intel 486-33.