Re: how to flush out cache.?

From: Steve Watt (steve_at_Watt.COM)
Date: 04/21/04

  • Next message: Julian Elischer: "Re: how to flush out cache.?" 
    Date: Wed, 21 Apr 2004 13:00:35 -0700
To: julian@elischer.org

    In article <Pine.BSF.4.21.0404211219460.31770-100000@InterJet.elischer.org> you write:
    >
    >Ok so I have an application where I need to
    >reread a file I have just written to ensure that it went to disk
    >correctly..
    >
    >Other than reading a few GB of data, is there a way to flush
    >out the cache copy of a file I've written?

    You can flush the file to disk with fsync(). But I don't think that
    evicts the blocks from the cache, just forces them to be written. To
    the disk controller's cache, if you're lucky.

    >possibilities include:
    >
    >a file flag saying "don't keep a copy after it's written to disk"?
    >a syscall discard_cached_blocks(fd);
    >
    >
    >?
    >any other suggestions?

    What are you hoping to accomplish? There are probably other ways
    to solve the larger problem. 

    -- 
Steve Watt KD6GGD  PP-ASEL-IA          ICBM: 121W 56' 57.8" / 37N 20' 14.9"
 Internet: steve @ Watt.COM                         Whois: SW32
   Free time?  There's no such thing.  It just comes in varying prices...
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  • Next message: Julian Elischer: "Re: how to flush out cache.?"

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