Re: silent semantic changes with reiser4

From: Pavel Machek (pavel_at_ucw.cz)
Date: 08/31/04

  • Next message: Adrian Bunk: "Re: [PATCH] embedding 2.6 or more findings on kernel size" 
    Date:	Tue, 31 Aug 2004 22:54:23 +0200
To: Linus Torvalds <torvalds@osdl.org>

    Hi!

    > > It buys me caching.
    >
    > I'll actually buy into that. If only because I consider caching to be one
    > of the more important things that the kernel does (caches are a _classic_
    > case of "shared data that needs synchronization").
    >
    > 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...

    chattr +kill-this-file-when-low-on-disk-space patch.bz2...ubz

    would solve first problem. Not sure how to do the second one.

                                                                    Pavel 

    -- 
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
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  • Next message: Adrian Bunk: "Re: [PATCH] embedding 2.6 or more findings on kernel size"

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