On 2/19/25 14:14, Rob Landley wrote:
On 2/19/25 11:24, Bernhard Voelker wrote:
On 2/10/25 2:34 PM, Matteo Croce wrote:
mu is a new tool which shows the amount of data that a set of files
are keeping into the cache.
mu uses the new cachestat() syscall introduced with Linux 6.5.
The GNU coreutils aim to be a platform independent implementation of a
certain
set of tools, most of them specified by POSIX.
Busybox has a "readahead" command under miscutils, which preloads a file
into disk cache. This seems like an option to readahead. (Maybe -s to
show size?)
...
I still think readahead -s makes sense here. You can tell Denys I said
so if you like. :)
I just checked and toybox also has readahead (well I never use it, I
added it in 2013 because somebody asked), but cachestat() was only added
in 2023 (linux commit cf264e1329fb) and my devuan install hasn't got
"man 2 cachestat" yet, nor is it in
https://man7.org/linux/man-pages/dir_section_2.html , which still says
6.10 not the new 6.11 from last week ala
https://www.spinics.net/lists/linux-man/msg29002.html but I'm not
spotting a mention of this syscall in that list's archives.
It might make sense to poke the man-pages project to to add a page for
the syscall before trying to get userspace to use it.
Rob
P.S. Also, "grep -r cachestat /usr/include" came up blank on my devuan
deadmau5 laptop, which has glibc 2.36, although musl commit dd690c490951
added it there (the syscall number, no libc wrapper yet), so I do have a
way to test it. But it still seems a bit unripe without a libc wrapper
to let you call it as a function...
