config CACHEFILES tristate "Filesystem caching on files" depends on FSCACHE && BLOCK help This permits use of a mounted filesystem as a cache for other filesystems - primarily networking filesystems - thus allowing fast local disk to enhance the speed of slower devices. See Documentation/filesystems/caching/cachefiles.txt for more information. config CACHEFILES_DEBUG bool "Debug CacheFiles" depends on CACHEFILES help This permits debugging to be dynamically enabled in the filesystem caching on files module. If this is set, the debugging output may be enabled by setting bits in /sys/modules/cachefiles/parameter/debug or by including a debugging specifier in /etc/cachefilesd.conf. config CACHEFILES_HISTOGRAM bool "Gather latency information on CacheFiles" depends on CACHEFILES && PROC_FS help This option causes latency information to be gathered on CacheFiles operation and exported through file: /proc/fs/cachefiles/histogram The generation of this histogram adds a certain amount of overhead to execution as there are a number of points at which data is gathered, and on a multi-CPU system these may be on cachelines that keep bouncing between CPUs. On the other hand, the histogram may be useful for debugging purposes. Saying 'N' here is recommended. See Documentation/filesystems/caching/cachefiles.txt for more information.