Abstract: Embodiments serve to balance overall performance of a finite-sized caching system having a first cache of a first cache size and a second cache of a second cache size. A tail portion and a head portion of each of the caches are defined wherein incoming data elements are initially stored in a respective head portion and wherein evicted data elements are evicted from a respective tail portion. Performance metrics are defined wherein a performance metric includes a predicted miss cost that would be incurred when replacing an evicted data elements. A quantitative function is defined to include cache performance metrics and a cache reallocation amount. The cache performance metrics are evaluated periodically to determine a then-current cache reallocation amount. The caches can be balanced by increasing the first cache size by the cache reallocation amount and decreasing the second cache size by the cache reallocation amount.

Abstract: Embodiments serve to balance overall performance of a finite-sized caching system having a first cache of a first cache size and a second cache of a second cache size. A tail portion and a head portion of each of the caches are defined wherein incoming data elements are initially stored in a respective head portion and wherein evicted data elements are evicted from a respective tail portion. Performance metrics are defined wherein a performance metric includes a predicted miss cost that would be incurred when replacing an evicted data elements. A quantitative function is defined to include cache performance metrics and a cache reallocation amount. The cache performance metrics are evaluated periodically to determine a then-current cache reallocation amount. The caches can be balanced by increasing the first cache size by the cache reallocation amount and decreasing the second cache size by the cache reallocation amount.

Abstract: In some embodiments, a system for testing performance of a virtualization environment comprises host machines, wherein each of the host machines comprises a hypervisor, one or more user virtual machines (UVMs) and a virtual machine controller, and one or more virtual disks comprising a plurality of storage devices. The one or more virtual disks may be accessible by the virtual machine controllers, and the virtual machine controllers conduct I/O transactions with the one or more virtual disks. The system may receive a specification of a hardware configuration for a host machine and configure the virtualization environment to incorporate the host machine. The system may then select one or more qualification tasks for a test scenario, execute the qualification tasks in the test scenario, and monitor performance of the virtualization environment. The system may then calculate a score assessing how well the hardware configuration may perform in the virtualization environment.