The RAM Enhanced Disk Cache Project (REDCAP)
Pilar González‐Férez, Juan Piernas, Toni Cortés · 2007
This paper presents the RAM Enhanced Disk Cache Project, REDCAp, a new cache of disk blocks which reduces the read 110 time by using a small portion of the main memory. The essential ideas behind REDCAP are to enlarge the built-in cache of the disk drive, imitate its behavior, and take advantage of its read-ahead mechanism by prefetching disk blocks. REDCAP is intended to be 110time efficient, and implements an activation-deactivation algorithm which turns its cache on and offdynamically depending on the 110 time improvement achieved. REDCAP has been implemented in the Linux kernel. The experimental results show that our proposal reduces the application time by up to 80%for workloads which exhibit some spatial locality, while it has the same peiformance as a traditional system for those workloads which have a random access pattern, or peifonn large sequential reads. 1.