Cache method for virtual storage devices

Abstract

The invention provides a cache method for virtual storage devices. A cache management module and a strategy module are added in the virtual storage device simulator of the traditional virtual machine monitor VMM. Firstly, when the virtual storage devices are created, the cache management module distributes respective independent cache for each virtual storage device; secondly, when the virtual storage devices are accessed, the strategy module appoints a prefetch strategy and a replacement strategy for the example of each virtual storage device and dynamically regulates the prefetch strategy. The cache method enables the hit rate of prefetched data to be increased, thereby further improving the access performance of the virtual storage devices.

Description

technical field [0001] A caching mechanism of a virtual storage device proposed by the present invention specifically relates to the fields of virtualization technology, caching technology and prefetch technology. Background technique [0002] Virtual machine technology has gradually become a research hotspot in the current industry and academia. The virtual machine monitor (VMM) implements hardware abstraction at the software layer, maps physical resources to multiple upper-layer guest operating systems, and virtualizes hardware resources. Realize running multiple operating systems at the same time and isolate them from each other. As one of the important hardware resources, the disk is bound to become the focus of attention when applying virtual technology to its storage field. The process of changing and converting the storage resources and storage management of the original storage entity by the new storage entity is called storage virtualization. Storage resources inclu...

AI Technical Summary

Problems solved by technology

This caching mechanism through shared cache has certain disadvantages. On the one hand, when virtual storage device A instance and virtual storage device B instance are accessed at the same time, it may happen that the cache of virtual storage device A instance is just put into the shared cache, and it may be virtualized. The cache replacement of the storage device B instance, and then the virtual storage device A instance will replace the cache of the virtual storage device B instance when the access misses. If this continues, the hit rate is extremely low, especially when multiple virtual storage devices are at the same time. On the other hand, although different virtual storage devices use corresponding prefetch strategies can greatly improve the hit rate, but the shared cache provides the same prefetch strategy for all virtual storage devices, which inevitably reduces the hit rate of prefetch

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