Science > Physics > - How Can I Invalidate the Floppy's Read Cache ? -
| Topic: |
Science > Physics |
| User: |
"Jeff Relf" |
| Date: |
13 Aug 2003 04:46:25 PM |
| Object: |
- How Can I Invalidate the Floppy's Read Cache ? - |
[ My posts aren't showing up , sorry if this is a repost . ]
I wrote :
" In Win98 ,
Does adding " VERIFY ON " to my AutoExec.BAT work ?
Does XCopy's /V switch _ Really _ work ?
Short of ejecting my floppy ( to force a bad read ) ,
Is there a way to invalidate the floppy's read cache ? "
Adding " SmartDrv A- /X " to AutoExec.BAT
seems to turn off A:'s read cache ,
But I can't do that on other people's machines .
( I say " Seems " because
I think the cache pops back on sometimes . )
Is there away to invalidate the read cache from a .BAT file ?
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| User: "Jeff Relf" |
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| Title: > Verify ON |
14 Aug 2003 04:42:03 AM |
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Hi " TV Slug " , You ask :
" Do you mean to flush out whatever is currently
in the cache from the floppy drive ? "
Yes . I don't want any caching . Read or Write .
A " SmartDrv A- /X " in AutoExec.BAT
_ Usually _ works on my Win98 machine .
But I can't do that on other people's machines .
Instead I have to force a bad read by ejecting the floppy .
I tested the caching with repeated " FC *.* A:\*.* " .
With caching , the second call is nearly instant . Bad .
Without caching , it takes a long time . Good .
" SmartDrv /S " reports on the lack of caching .
You say :
" Because I don't think you can accomplish that
with just a .BAT file under Windows98 . "
That must be right , I can't find the answer anywhere .
Do you know if the undocumented /V switch works in XCopy ?
Does the " Verify ON " command work ?
You mention :
" You can disable the write-behind for all removable
drives though . "
Whoopie !
Why doesn't Win98 give the option
to turn off the read cache too ? Bastards !
P.S. Sorry about all the reposts .
I can post using 3 NNTP servers
and they were all very unstable yesterday .
( Or was it my ISP ? )
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| User: "Jeff Relf" |
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| Title: - I Answered - |
14 Aug 2003 12:33:37 PM |
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I asked :
" Do you know if the undocumented /V switch works in XCopy ?
Does the " Verify ON " command work ? "
XCopy's /V switch definitely works .
" Verify ON " does not .
" FC *.* A:\*.* "
works in a .BAT file _ Only _
if it's preceded by a " Pause " .
So there's no need to have
" SmartDrv A- /X " in anyone's AutoExec.BAT file .
( To turn off " Read Caching " . )
Here's how I know :
I have a floppy that always got bad data when I
use the Win98 GUI to copy a large file to it .
I did a " Thorough Surface Check " on it . It's fine .
But XCopy always worked when the /V switch was used .
( That's V for Verify )
But , in a .BAT file , the FC did nothing ,
even if I did twenty of them .
Placing a " Pause "
between the XCopy and the FC made the FC work .
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| User: "john bailo" |
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| Title: do you wear a little rear view mirror on your glasses ? |
15 Aug 2003 12:39:32 AM |
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Jeff Relf:
Placing a " Pause "
between the XCopy and the FC made the FC work .
only a true geek would 'rescue a floppy'
--
dean '04
http://deanforamerica.com
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| User: "Jeff Relf" |
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| Title: - Three Questions - |
15 Aug 2003 09:08:45 AM |
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Apparently Win98 has two read-caches for floppy disks :
One of which times out after about four seconds .
Here are three questions for you Johnny :
Q. Are either of these two caches documented anywhere ?
A. Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Aaaaahhh .
Q. Is there anyway to turn off
either of these two read-caches ?
( Preferably from a batch file . )
A. Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Aaaaahhh .
Q. Is there anyway to
make the Win98 GUI verify it's copies ?
A. Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Aaaaahhh .
Johnny says :
" Only a true geek would ' rescue a floppy ' . "
Floppies are my only backups .
The Win98 GUI copies were secretly munging my backups .
Every ***** Time !
( The floppy is good ,
I did two thorough surface checks . )
And I couldn't create a batch file to
simply copy and verify the copy .
As it turns out , I think there are two floppy disk caches :
- An expiring cache that
expires about four seconds after an XCopy .
FC must be made to wait for this one to expire .
- A non-expiring cache that doesn't timeout .
Unlike most other programs , FC looks past this cache .
Because when I do :
XCopy MegaFile.DAT A: /V
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
The expiring cache _ Unquestionably _
causes the FC lines to not access the floppy disk ...
It just zips through all five FC lines .
The solution was to place a four second pause between
the XCopy and the FC .
DOS has no way to do a four second pause ,
so I just do a Dir of the entire disk to Nul :
XCopy MegaFile.DAT A: /V
Dir \*.* /S >Nul
FC MegaFile.DAT A:\*.*
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| User: "Jeff Relf" |
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| Title: - Oh well - |
15 Aug 2003 06:47:42 PM |
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Hi Double-A , You say :
" You might try fiddling with the Performance Options
under System on the Control Panel under Settings . "
I tried that . Nothing works .
Win98 obviously doesn't provide a way to alter
either of the floppy disk's two read caches .
( Especially not in a batch file ... Or even in C++ ? )
Commode.OBJ will let a C++ program flush
the _ Write _ cash , but not the read cache .
Nor are these caches documented anywhere .
( As far as I can tell . )
It's be nice if Win98 GUI verified all of it's copies .
Oh well .
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| User: "Jeff Relf" |
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| Title: Bad DRAM ? |
16 Aug 2003 12:00:13 AM |
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I wrote :
" The Win98 GUI copies were secretly munging my backups . "
It just occurred to me that the corrupted copies I get when
using the Win GUI to copy files could be due to bad DRAM !
The bad copies don't happen when I use DOS to copy files .
And the corrupted files have bad
bytes scattered here and there .
Is there away to check the integrity of my DRAM ?
Maybe I need to update my BIOS .
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| User: "Jeff Relf" |
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| Title: Re: Bad DRAM ? |
16 Aug 2003 01:56:33 AM |
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I asked :
" Is there away to check the integrity of my DRAM ? "
My RAM is fine .
I ran a thorough check using the free
" DocMemory PC Memory Diagnostic Software " .
http://www.simmtester.com/page/products/doc/docfeat.asp
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| User: "=^.^=" |
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| Title: Re: Bad DRAM ? |
16 Aug 2003 12:30:35 AM |
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On 16 Aug 2003 05:00:13 GMT, Jeff Relf <____Jeff-Relf@NCPlus.NET>
wrote:
Is there away to check the integrity of my DRAM ?
Maybe I need to update my BIOS .
place your OS and static applications on a 2 gig partition
....primary boot worx for me
put applications with dynamic data on another volume
put the temps, IEX caches, etc. on another, and scuff
all the unneeded helpfiles, bitmaps, and other bloat
swap/pagefile should go on the rim of another drive
get it to the config you want and run Spybot S&D +
AdAware, RegClean, and other paring knives on it
reboot into DOS and run Norton Ghost 5.1d...
do a crc on the Ghost file, and then burn a copy
to CDR. the High compression setting does 2:1
do a crc on the CDR image, just-in-case...
keep incrementing a local clean image as the installation
matures, and occasionally save a good image of that to CDR
this will save plenty of fixit time, to waste on admin. tasking
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| User: "Jeff Relf" |
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| Title: How do I do a CRC ? |
16 Aug 2003 02:01:14 AM |
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Hi =^.^= , You say :
" Do a crc on the Ghost file . "
I don't think I have any viruses .
I pretty much know everything that's on my system .
How do I do a CRC on a file ?
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| User: "=^.^=" |
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| Title: Re: How do I do a CRC ? |
16 Aug 2003 02:43:22 AM |
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On 16 Aug 2003 07:01:14 GMT, Jeff Relf <____Jeff-Relf@NCPlus.NET>
wrote:
Hi =3D^.^=3D , You say :
" Do a crc on the Ghost file . "
I don't think I have any viruses .
I pretty much know everything that's on my system .
that's when you Ghost an image, to use to overwrite the
fucked-up install and restore a clean working version...
How do I do a CRC on a file ?
go to Image Check to check if the CRC is correct
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| User: "42" |
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| Title: Re: - Three Questions - |
15 Aug 2003 01:43:10 PM |
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You might try using WinZip or pkzip for your backups. Easy to use plus
both can span more than one floppy and support long file names.
Just wondering, are those 5-1/4 inch floppies?
"Jeff Relf" <____Jeff-Relf@NCPlus.NET> wrote in message
news:Xns93D848D70BDF3Relf@130.133.1.4...
Apparently Win98 has two read-caches for floppy disks :
One of which times out after about four seconds .
Here are three questions for you Johnny :
Q. Are either of these two caches documented anywhere ?
A. Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Aaaaahhh .
Q. Is there anyway to turn off
either of these two read-caches ?
( Preferably from a batch file . )
A. Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Aaaaahhh .
Q. Is there anyway to
make the Win98 GUI verify it's copies ?
A. Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Ha ! Aaaaahhh .
Johnny says :
" Only a true geek would ' rescue a floppy ' . "
Floppies are my only backups .
The Win98 GUI copies were secretly munging my backups .
Every ***** Time !
( The floppy is good ,
I did two thorough surface checks . )
And I couldn't create a batch file to
simply copy and verify the copy .
As it turns out , I think there are two floppy disk caches :
- An expiring cache that
expires about four seconds after an XCopy .
FC must be made to wait for this one to expire .
- A non-expiring cache that doesn't timeout .
Unlike most other programs , FC looks past this cache .
Because when I do :
XCopy MegaFile.DAT A: /V
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
FC MegaFile.DAT A:\*.*
The expiring cache _ Unquestionably _
causes the FC lines to not access the floppy disk ...
It just zips through all five FC lines .
The solution was to place a four second pause between
the XCopy and the FC .
DOS has no way to do a four second pause ,
so I just do a Dir of the entire disk to Nul :
XCopy MegaFile.DAT A: /V
Dir \*.* /S >Nul
FC MegaFile.DAT A:\*.*
.
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| User: "=^.^=" |
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| Title: Re: - I Answered - |
14 Aug 2003 04:32:36 PM |
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On 14 Aug 2003 17:33:37 GMT, Jeff Relf <____Jeff-Relf@NCPlus.NET>
wrote:
I asked :
" Do you know if the undocumented /V switch works in XCopy ?
Does the " Verify ON " command work ? "
XCopy's /V switch definitely works . =20
" Verify ON " does not .
that's a DOS command processer internal
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| User: "davidoff404" |
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| Title: Re: - How Can I Invalidate the Floppy's Read Cache ? - |
13 Aug 2003 05:50:56 PM |
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Regardless of how plausible you try to make your terminology seem, it's
obvious to everyone with more than a passing interest in operating systems
that you're talking horseshit.
Maybe you should read up on MSDOS string parsing before posting such tripe
again.
davidoff
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| User: "Jeff Relf" |
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| Title: - 404 Needs a Picture ? - |
13 Aug 2003 07:36:30 PM |
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Hi there " David Off 404 " ,
You say :
" Maybe you should read up on MSDOS string
parsing before posting such tripe again . "
Try as I might ,
I have no idea what your babbling about .
I'm just looking for a better way to invalidate the
floppy's " Read Cache " in Win98 .
Do you need me to draw you a picture ?
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