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Re: Why does it take less than 3 seconds to make the second copy of the 4 gig file ?

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Michael Moroney wrote:

> Peter =?UTF-8?B?S8O2aGxtYW5u?= <peter-koehlmann@t-online.de> writes:
> 
>> wrote:
> 
>>> After a ReBoot, it takes 11 seconds to copy a 4 gig file
>>> to/from my TeraByte Samsung 850 EVO; after that,
>>> it takes _less_ than 3 seconds to copy it again.   Why ?
> 
>>Because it is buffered in your memory, you clueless dimbulb.
>>And no, it does *not* take just 3 seconds. You will need 7 seconds for the
>>operation to finish, even though the OS might tell you earlier that its
>>done (because of buffering). You simply can't bypass the physical
>>limitations, and those are around 500 MB/sec. In other words: The
>>operation will take 7 seconds, not 3, you idiot
> 
> The difference between "write back caching" and "write through caching".
> On a write, a disklike device (actual hard drive, RAID controller, Flash)
> with cache can tell the OS "success" upon a write as soon as it gets the
> data into its cache, or it can wait until the data is all safely onto
> non-volatile media before returning success to the OS.  The first is much
> faster than the second, but the second is much safer, in case something
> goes wrong (such as a power failure at the wrong time in a poorly designed
> system)

Not only just that. That cretinous dimbulb "Relf" (a very typical wintendo 
luser, dumb beyond any imagination) "tests" his drive with *one* copy of a 
large file. If he repeats that with a copy of several large files at once, 
he will see how long it really takes, because then the buffering will not 
work any more like it does with just one file

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The Inevitable Death of the Windows PC Homer <usenet@slated.org> - 2016-04-20 11:06 +0100
  Re: I don't have to hold no fucking phone. Homer <usenet@slated.org> - 2016-04-20 11:57 +0100
    Re: I don't have to hold no fucking phone. Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-20 13:49 +0200
      Re: I don't have to hold no fucking phone. DFS <nospam@dfs.com> - 2016-04-20 10:07 -0400
        Re: I don't have to hold no fucking phone. Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-20 19:12 +0200
          Copying a 3.5 gig file, locally, SATA III is not a (limiting) factor. Jeff-Relf.Me <@.> - 2016-04-20 11:57 -0700
            Re: Copying a 3.5 gig file, locally, SATA III is not a (limiting) factor. Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-20 23:42 +0200
              Copying a 3.5 gig file from/to the Samsung 850 EVO isn't SATA III limited. Jeff-Relf.Me <@.> - 2016-04-20 14:55 -0700
                Re: Copying a 3.5 gig file from/to the Samsung 850 EVO isn't SATA III limited. Melzzzzz <mel@zzzzz.com> - 2016-04-21 00:04 +0200
                Why does it take less than 3 seconds to make the second copy of the 4 gig file ? Jeff-Relf.Me <@.> - 2016-04-20 17:08 -0700
                Re: Why does it take less than 3 seconds to make the second copy of the 4 gig file ? Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-21 09:00 +0200
                Re: Why does it take less than 3 seconds to make the second copy of the 4 gig file ? moroney@world.std.spaamtrap.com (Michael Moroney) - 2016-04-21 17:00 +0000
                Re: Why does it take less than 3 seconds to make the second copy of the 4 gig file ? Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-21 19:05 +0200
            Re: Copying a 3.5 gig file, locally, SATA III is not a (limiting) factor. Incubus <incubus9536612@gmail.com> - 2016-04-22 06:07 -0700
          Re: I don't have to hold no fucking phone. DFS <nospam@dfs.com> - 2016-04-22 10:09 -0400
            The first copy ( of a 4 gig file ) takes 11 seconds. Jeff-Relf.Me <@.> - 2016-04-22 11:55 -0700
              Re: The first copy ( of a 4 gig file ) takes 11 seconds. Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-22 23:27 +0200
                Re: The first copy ( of a 4 gig file ) takes 11 seconds. Richard King <kingsley651@webby.org> - 2016-04-22 17:55 -0400
                Re: The first copy ( of a 4 gig file ) takes 11 seconds. Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-23 00:05 +0200
                Re: The first copy ( of a 4 gig file ) takes 11 seconds. Richard King <kingsley651@webby.org> - 2016-04-22 18:20 -0400
                Re: The first copy ( of a 4 gig file ) takes 11 seconds. Peter Köhlmann <peter-koehlmann@t-online.de> - 2016-04-23 01:01 +0200
                Re: The first copy ( of a 4 gig file ) takes 11 seconds. Richard King <kingsley651@webby.org> - 2016-04-22 19:11 -0400
    Re: I don't have to hold no fucking phone. chrisv <chrisv@nospam.invalid> - 2016-04-20 07:05 -0500
      Re: I don't have to hold no fucking phone. Sandman <mr@sandman.net> - 2016-04-20 12:28 +0000
    Re: The subjective preferences of the dying minority Homer <usenet@slated.org> - 2016-04-20 13:58 +0100
  Re: The Inevitable Death of the Windows PC DFS <nospam@dfs.com> - 2016-04-20 10:18 -0400
  Re: The Inevitable Death of the Windows PC ronb <ronb02NOSPAM@gmail.com> - 2016-04-20 17:09 +0000
    Re: The Inevitable Death of the Windows PC Me Sham <osirus47@yahoo.com> - 2016-04-20 10:38 -0700
      Re: The Inevitable Death of the Windows PC Desk Rabbit <me@example.com> - 2016-04-22 12:11 +0100
  Re: The Inevitable Death of the Windows PC 7 <7@enemygadgets.com> - 2016-04-20 20:51 +0000
  Re: The Inevitable Death of the Windows PC JEDIDIAH <jedi@nomad.mishnet> - 2016-04-20 15:53 -0500
    Re: The Inevitable Death of the Windows PC 7 <7@enemygadgets.com> - 2016-04-20 22:01 +0000
      Re: The Inevitable Death of the Windows PC Desk Rabbit <me@example.com> - 2016-04-22 12:14 +0100
        Re: The Inevitable Death of the Windows PC GreyCloud <mist@cumulus.com> - 2016-04-22 16:37 -0600

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