how to flush out cache.?
steve at Watt.COM
Wed Apr 21 13:37:51 PDT 2004
On Apr 21, 13:28, Julian Elischer wrote:
} Subject: Re: how to flush out cache.?
} On Wed, 21 Apr 2004, Steve Watt wrote:
} > In article <Pine.BSF.4.21.0404211219460.31770-100000 at 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..
} > What are you hoping to accomplish? There are probably other ways
} > to solve the larger problem.
} I thought I was being clear..
} I need to remove all the pages from cache so that a reread of the file
} is forced to go to disk.
} and I don't want to go read a 2GB dummy file to force the flush..
No, my question is "what are you trying to accomplish with the
reread", at a higher level than "I want to know it's on disk". Is
there some reason you have for not trusting the hardware? Are you
trying to do a database commit protocol? Debugging the storage
} Someone suggested that I read the file usign 'dump' through the raw
Even doing that doesn't necessarily mean the bits have made it onto
the rotating media. There can also be caches in the disk controller,
and/or caches on the drive itself. If you're trying for a case where
you want to pull the power, unmounting and remounting the filesystem
will get it about as close as you can.
Steve Watt KD6GGD PP-ASEL-IA ICBM: 121W 56' 57.8" / 37N 20' 14.9"
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