[PATCH] fadvise(2) system call

[Alfred Perlstein]

* Garrett Cooper <yanegomi at gmail.com> [111104 10:19] wrote:
> On Nov 4, 2011, at 9:03 AM, Alfred Perlstein wrote:
> 
> > * John Baldwin <jhb at FreeBSD.org> [111103 19:38] wrote:
> >> On 11/2/11 1:20 PM, Alfred Perlstein wrote:
> >>> * John Baldwin<jhb at freebsd.org>  [111102 11:05] wrote:
> >>>> On Tuesday, November 01, 2011 7:56:48 pm Bruce Cran wrote:
> >>>>> On 01/11/2011 17:08, John Baldwin wrote:
> >>>>>> I had found it via the web: http://linux.die.net/man/2/fadvise
> >>>>>> However, after further searching it appears to be stale (if you follow
> >>>>>> it's cross-reference to madvise(2), that page only has links to
> >>>>>> posix_fadvise() and not fadvise()).
> >>>>> 
> >>>>> There's
> >>>>> http://www.speedware.com/HPe3000_resources/MPE_to_HP-UX_cross-
> >>>> reference/system_administration_cross-reference/cmd.html?cmdid=MS_1800
> >>>>> for HP-UX ("*fadvise()* was derived by HP from the IEEE POSIX
> >>>>> 1003.1-2001 Standard"), though it also has posix_fadvise.
> >>>> 
> >>>> Hmm, that one actually has an extra argument.  I'll just go with
> >>>> posix_fadvise() for now.  Interesting that HP lets you OR together
> >>>> two policies (so you can say both "I will access this file sequentially
> >>>> and with noreuse").
> >>> 
> >>> Makes sense for gzip/tar.
> >> 
> >> Ehh, quite possibly not for something that generic.  I think you only
> >> want to do this if you have very specific knowledge about your access
> >> pattern, and I do not think they are generically applicable.
> > 
> > You often spend time untarring the same tarball over and over 
> > in your workflow John?
> 
> This is starting to sound like something that libarchive / pkg_install would benefit from (jkh pkg_install or pkgng).
> -Garrett

It seems a no brainer to flip the bit on when reading an archive that's as large as main memory.

It's annoying to untar something, then have my box have to page back in all programs.


-- 
- Alfred Perlstein
.- VMOA #5191, 03 vmax, 92 gs500, 85 ch250, 07 zx10
.- FreeBSD committer