Title
CMD: classification-based memory deduplication through page access characteristics
Abstract
Limited main memory size is considered as one of the major bottlenecks in virtualization environments. Content-Based Page Sharing (CBPS) is an efficient memory deduplication technique to reduce server memory requirements, in which pages with same content are detected and shared into a single copy. As the widely used implementation of CBPS, Kernel Samepage Merging (KSM) maintains the whole memory pages into two global comparison trees (a stable tree and an unstable tree). To detect page sharing opportunities, each tracked page needs to be compared with pages already in these two large global trees. However since the vast majority of compared pages have different content with it, that will induce massive futility comparisons and thus heavy overhead. In this paper, we propose a lightweight page Classification-based Memory Deduplication approach named CMD to reduce futile page comparison overhead meanwhile to detect page sharing opportunities efficiently. The main innovation of CMD is that pages are grouped into different classifications based on page access characteristics. Pages with similar access characteristics are suggested to have higher possibility with same content, thus they are grouped into the same classification. In CMD, the large global comparison trees are divided into multiple small trees with dedicated local ones in each page classification. Page comparisons are performed just in the same classification, and pages from different classifications are never compared (since they probably result in futile comparisons). The experimental results show that CMD can efficiently reduce page comparisons (by about 68.5%) meanwhile detect nearly the same (by more than 98%) or even more page sharing opportunities.
Year
DOI
Venue
2014
10.1145/2576195.2576204
VEE
Keywords
Field
DocType
classification-based memory deduplication,efficient memory deduplication technique,tracked page,page classification,whole memory page,futile page comparison overhead,lightweight page,limited main memory size,page access characteristic,different classification,page comparison
Kernel (linear algebra),Virtualization,Computer science,Page attribute table,Page replacement algorithm,B-heap,Merge (version control),Database,Memory deduplication
Conference
Volume
Issue
ISSN
49
7
0362-1340
Citations 
PageRank 
References 
19
0.85
20
Authors
6
Name
Order
Citations
PageRank
Licheng Chen11039.74
Zhipeng Wei2191.52
Zehan Cui319710.00
Ming-yu Chen490279.29
Haiyang Pan5317.92
Yungang Bao636131.11