This is the command nocache that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator
PROGRAM:
NAME
nocache - don't use Linux page cache on given command
SYNOPSIS
nocache [-n <n>] command [argument...]
OPTIONS
-n <n> "Set number of fadvise calls"
Execute the `posix_fadvise` system call <n> times in a row. Depending on your
machine, this might give better results (use it if in your tests `nocache` fails to
eradicate pages from cache properly).
DESCRIPTION
The `nocache` tool tries to minimize the effect an application has on the Linux file
system cache. This is done by intercepting the `open` and `close` system calls and calling
`posix_fadvise` with the `POSIX_FADV_DONTNEED` parameter. Because the library remembers
which pages (ie., 4K-blocks of the file) were already in file system cache when the file
was opened, these will not be marked as "don't need", because other applications might
need that, although they are not actively used (think: hot standby).
Use case: backup processes that should not interfere with the present state of the cache.
Use nocache online using onworks.net services
