Can anyone recommend a way to read a file ensuring that it is not coming from file cache on Linux?
I'm trying to write a metric script for measuring http connect + read times from a web server over localhost. I want to plot both file cache read times and non-cached files. I thought of simply opening and writing to the file to dirty it's pages, but there no guarantee that pdflush will have already written the dirty pages to disk -pretty sure it depends on all the dirty ratio and intervals. Does anybody know of a system call that will 'knock' the file out of file cache? Can madvise or fadvise do this? I know this is mostly a unix question, but I'm asking in the context of how to do this in python. -- http://mail.python.org/mailman/listinfo/python-list
