Re: silent semantic changes with reiser4

From: Linus Torvalds (torvalds_at_osdl.org)
Date: 08/31/04

  • Next message: David S. Miller: "Re: ALSA update broke Sparc" 
    Date:	Tue, 31 Aug 2004 13:59:45 -0700 (PDT)
To: Pavel Machek <pavel@ucw.cz>

    On Tue, 31 Aug 2004, Pavel Machek wrote:
    > >
    > > However, that said, user space can trivially cache things in the
    > > filesystem, so while this may be a convenient feature, I think you should
    > > look at perhaps doing it in the _shell_ instead..
    >
    > That cache should disappear as soon as I need disk
    > space. I.e. userspace should never see -ENOSPC because of this kind of
    > caching. This need some kernel support. Ouch and cached file should
    > atomically go away as soon as main file changes, otherwise I do not
    > see how multiple processes could cooperate on caching...

    Well, what other projects have done is to just reserve a certain amount of
    disk for caching. See "ccache", which solves both of the above problems
    (it doesn't shrink the cache on ENOSPC, but reserving diskspace is
    accepted practice for things like this..)

                    Linus
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

  • Next message: David S. Miller: "Re: ALSA update broke Sparc"

    Relevant Pages

    • Re: nasm over gas?
      ... While it may not benefit from caching, cache misses still hurt it. ... Why has Alan measured faster kernels with -Os than with -O2? ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • Re: Block Device Caching
      ... > data does not go into any cache. ... > This lead us to the conclusion that block devices do not cache, ... > while when unmounting the partition, caching does not work. ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • Re[2]: [PHP] dynamic -> static
      ... As I wrote already this issue is mainly because of search engines ... incompatibility with dynamic content sites (to be more exact - with ... You can cache your code using PHP Accelerator or Turck ... MM> implementing a caching layer between your application and your database. ...
      (php.general)
    • Re: [PHP] Aggressive PHP Smart Caching
      ... i have begun to experiment w/ your caching tool. ... it is also important that the script calling ob_end_flushhave access to ... the header method in the first bit of code in the cache tool. ...
      (php.general)
    • Re: [PHP] dynamic -> static
      ... You can cache your code using PHP Accelerator or Turck ... implementing a caching layer between your application and your database. ... 404 causes it to error out regardless of the content of the response. ... with any caching system as above - finding and flushing stale data. ...
      (php.general)