Evaluating the Effectiveness of REDCAP to Recover the Locality Missed by Today´s Linux Systems

In order to know how different conditions influence the behavior of the RAM Enhanced Disk Cache Project (RED-CAP), we have analyzed the impact of the file system and the REDCAP cache size. The results show that, for work-loads which exhibit some spatial locality the application time can be reduced by more than 80% for file systems that split the disk into block groups, while for those that do not use this division the reduction can be more than 55%. REDCAP has the same performance as a traditional system for those workloads with a random or sequential access pattern. The experiments also show that the cache size can determine the results, depending on the file system and the number of processes.