Re: [Freedos-user] Disk checking and defragmentation

[Eric A. <e....@jp...>]

Hi Christian, Marcos

I do not know how DOSLFN interacts with CHKDSK and whether
we are talking about errors created by DOSLFN alone and
detected by CHKDSK later or about errors created by some
effect of having DOSLFN loaded why CHKDSK runs but...

Having HIMEM and LBACACHE active helps a lot with the
speed of DOSFSCK as far as I remember :-).

Note that NDN or FileWizard might cause some troubles
when used in together with DOSLFN etc, you never know?

I think NDN had some direct disk access option which
sometimes caused problems with caches/DOSLFN/ramdisk?

>> hundreds of damaged files. In addition, strange folders or files
>> appeared which could not be deleted. To get rid of them I had to

Please explain what you mean by strange... You should
also be able to drop bad items with CHKDSK / DOSFSCK.

>>   dosfsck 2.11.DOS3, 8 Aug 2007, FAT32, LFN
>>   Starting check/repair pass.
>>   Starting verification pass.
>>   c:: 33412 files, 42820/65505 clusters

Only if you use one of the "repair" options then
the first pass will check the original disk, the
second pass will check what will happen with the
suggested changes and after that pass it asks
you whether to write changes to disk. You should
also consider using the "verbose" option :-).

Usual options can be:

dosfsck -v -V -a c:
dosfsck -v -V -r c:

Notice that you can also give diskimage file
names instead of drive letters as far as I
remember. Also notice that if no errors are
detected, dosfsck will of course not ask you
whether and how to repair them either :-).

>> That confused me. Does it mean the disk is OK?

Yes

>> Is there anything else to be done?

You might want to defrag it but that is a
completely different story. Also it takes
ages to do full defrag on big disks but
the current version also has some modes
which "only defrag a bit" at your choice.

> Yes, such a screen means DOSFSCK didn't find any error either in it's  
> first pass or in the verification pass. I usually run DOSFSCK with the -r  
> and -t options too, which enable interactive operation (DOSFSCK will  
> prompt you what to do on errors) and testing whether clusters are bad.

Testing for bad clusters means that DOSFSCK
will test-read all files and also all unused
clusters, so it takes much longer. Also, a
modern harddisk will use SMART for self-check
of health anyway, so surface scans are a bit
a thing of the past for harddisks :-).

> Your appended NSSI report says there's no XMS (HIMEM) or EMS (EMM386)  
> driver installed. Is that your usual configuration? This might cause  
> problems. I think DEFRAG and software ported to DJGPP (such as DOSFSCK)  
> might run better with XMS than with "raw" extended memory.

I agree :-) You also have much more DOS RAM free if you
use HIMEMX and DOS=HIGH in your config (or fdconfig) sys
because that allows kernel and command.com to load into
HMA and swap to XMS, respectively.

Eric



PS: If your DOSFSCK runs very slow and you have file damage
afterwards then maybe you used a strange DOS extender / DPMI
which swaps to (the scanned) disk when running out of RAM?
DOSFSCK 2.11.DOS3 explicitly tells CWSDPMI to disable this
but very old DOSFSCK versions did not have that feature.