Re: [PATCH 00/19] Adaptive read-ahead V8

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Fri, Nov 25, 2005 at 04:43:17PM +0100, Diego Calleja wrote:
> Recently, a openoffice hacker wrote in his blog that the kernel was
> culprit of applications not starting as fast as in other systems.
> Most of the reasons he gave were wrong, but there was a interesting
> one: When you start your system, you've lots of free memory. Since
> you have lots of memory, he said it was reasonable to expect that
> kernel would readahead *heavily* everything it can to fill that
> memory as soon as possible (hoping that what you readahead'ed was
> part of the kde/gnome/openoffice libraries etc) and go back to the
> normal behaviour when your free memory is used by caches etc.
> "Teorically" it looks like a nice heuristic for desktops. Does
> adaptative readahead does something like this?

It's interesting ;)
In fact some distributions do have a read-ahead script to preload files on
startup. The readahead system call should be enough for this purpose:

NAME
       readahead - perform file readahead into page cache

SYNOPSIS
       #include <fcntl.h>

       ssize_t readahead(int fd, off64_t *offset, size_t count);

Thanks,
Wu
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux