Enhancing Memory Deduplication Using Temporal Page Sharing Behaviors in Virtual Environments

Abstract

The performance and scalability of the virtualized systems are affected by the size and speed of main memory. The memory deduplication is a prominent approach which increases memory savings by sharing of duplicate memory pages across virtual machines. Stability of shared pages is the important factor for page sharing mechanism. If sharing is short lived, it triggers CoW exception handler instantly which significantly impact the performance of memory deduplication process. The proposed approach uses hinting mechanism to evade instability pages from scanning and merging process, thereby enhancing the effectiveness and efficiency of memory deduplication process. The main advantage of proposed approach is that it does not need any guest OS modification and it is implemented using Kernel Samepage Merging (KSM) - a memory deduplication daemon in the linux kernel. The evaluation with several benchmark workloads shows that the proposed approach achieves a significant improvement over vanilla KSM memory deduplication process.KeywordsMemory DeduplicationVirtualizationServer ConsolidationKSMPage Sharing