Re: GSoC-2016

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Thu, Jun 02, 2016 at 11:48:18AM +0530, HRISHIKESH GOYAL wrote:
> 
> another generic problem that will help me considerably is I want to
> disable/clear cache memory. I want corresponding to each command in
> userland, there is  lower level disk read. Which will help me in tracing fs
> routines.

This will never happen.  You won't even see requests of the same size, because
the VM system translates them into ranges of pages and reads ahead/writes
behind.

About the best you can do is write a test program that uses mmap and
madvise(MADV_RANDOM), then touches one page at a time.  But then you will
never see anything but page-sized I/O requests, which may also not be
what you want.

Thor