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Micky
February 1st 17, 06:15 PM
Three major topics about cloning


1) Took 30 hours to make a first clone of a 90 gig partition. Some time
later I made an incremantal update of that clone partition. During that
time, my partition displayed as Unallocated, so I had no access to any
of its files for 30 hours. If there had been a crash, power failure, or
if my delinquent nephew had turned off the computer, I think my clone
would have disappeared, become unallocated space no matter what files
were in it, and it would take 30 more hours from the time I noticed to
make another one. During which time something might go wrong with the
System drive. This all sounds very risky. What am I missing?

Also, they said an incremental update would run faster, but it had only
done 20% in about 8 hours, which extrapolated to 40 hours. Not
remembering that this was a semi-reasonable value, I cancelled the clone
and the partition was labeled Unallocated!! That's how I know what I
said in the previous paragraph.

But in addition, it said the incremental clone would be much faster than
the original clone, and it was no faster, probably slower.

Think about it. For the original clone all it has to do is read a
secton and write the same sector to the second drive. To do an
incremental clone, IIUC it has to read the sector on the old drive, read
the sector on the new drive, compare the two, and if they dont' match,
write the sector; That's one or two extra steps! Or is there a flag
that shows a sector has been changed. And if there is and if that
helps, why was my incremental backup running so slowly; Not that much
had been changed, although when files get rewritten in normal computer
operation, arent' they likely to change 2 source sectors or more, the
one(s) they were in and the one(s) they are written to?


2) Using different software products sequentially. It seems to me that
if a clone program makes a real clone, there is no evidence of which
program made it (except that the installed program and maybe its log
will be copied too). But it seems to me that none of that would
prevent any other incremental clone program from applying incremental
changes of the, say, C: partition to the clone. That I could use the
program I like most for initial cloning, say once a month, and use the
program I like most or any functioning program for intermediate,
incremental clones. Right?


3) When the process was done, even though I only asked to clone one
partition, I had allocated space in 3 parttions, and it had copied all 3
partitions, the Win10 partition and a tiny one before and after it.
None of them were labeled active in the partition manager, so I used it
to make the first one active.

But still none are labeled Boot or System. Do I need to do something to
make them bootable, like run EasyBCD. I thought that cloning them
would do all this. Since that seems to me the meaning of clone.

Paul[_32_]
February 1st 17, 06:38 PM
micky wrote:
> Three major topics about cloning
>
>
> 1) Took 30 hours to make a first clone of a 90 gig partition. Some time
> later I made an incremantal update of that clone partition. During that
> time, my partition displayed as Unallocated, so I had no access to any
> of its files for 30 hours. If there had been a crash, power failure, or
> if my delinquent nephew had turned off the computer, I think my clone
> would have disappeared, become unallocated space no matter what files
> were in it, and it would take 30 more hours from the time I noticed to
> make another one. During which time something might go wrong with the
> System drive. This all sounds very risky. What am I missing?
>
> Also, they said an incremental update would run faster, but it had only
> done 20% in about 8 hours, which extrapolated to 40 hours. Not
> remembering that this was a semi-reasonable value, I cancelled the clone
> and the partition was labeled Unallocated!! That's how I know what I
> said in the previous paragraph.
>
> But in addition, it said the incremental clone would be much faster than
> the original clone, and it was no faster, probably slower.
>
> Think about it. For the original clone all it has to do is read a
> secton and write the same sector to the second drive. To do an
> incremental clone, IIUC it has to read the sector on the old drive, read
> the sector on the new drive, compare the two, and if they dont' match,
> write the sector; That's one or two extra steps! Or is there a flag
> that shows a sector has been changed. And if there is and if that
> helps, why was my incremental backup running so slowly; Not that much
> had been changed, although when files get rewritten in normal computer
> operation, arent' they likely to change 2 source sectors or more, the
> one(s) they were in and the one(s) they are written to?
>
>
> 2) Using different software products sequentially. It seems to me that
> if a clone program makes a real clone, there is no evidence of which
> program made it (except that the installed program and maybe its log
> will be copied too). But it seems to me that none of that would
> prevent any other incremental clone program from applying incremental
> changes of the, say, C: partition to the clone. That I could use the
> program I like most for initial cloning, say once a month, and use the
> program I like most or any functioning program for intermediate,
> incremental clones. Right?
>
>
> 3) When the process was done, even though I only asked to clone one
> partition, I had allocated space in 3 parttions, and it had copied all 3
> partitions, the Win10 partition and a tiny one before and after it.
> None of them were labeled active in the partition manager, so I used it
> to make the first one active.
>
> But still none are labeled Boot or System. Do I need to do something to
> make them bootable, like run EasyBCD. I thought that cloning them
> would do all this. Since that seems to me the meaning of clone.

So right away, you know the performance level is *way way off*
and something is near to failing.

If you have a SMART utility (the Health tab in HDTune 2.55
will do), check the Reallocated on both the source and
destination drives.

If you cancel a clone, a utility should prevent "half-finished"
partitions from being offered to you. You would not want
a half-finished work of art. You would have no way of
knowing what files were missing. For safety, it should
remove the partitions from the partition table on the
destination, to ensure you don't make any mistakes
about "successful" copies.

You can clone single partitions. You can put them on the
end of several partitions already on the target (you can
even drag and drop them). If the clone is prematurely
terminated, the utility has to be careful to not make
any of the "stable" partitions disappear.

I would also be running CHKDSK on the source partition,
in the mode of operation that read-verifies every
sector. Or, barring that, even using HDTune benchmark
or HDTune Error Scan and watching the transfer rates
involved, should tell you whether either the source
or destination disk is near death.

An older SATA might be 65MB/sec on the outer diameter
of the disk. A newer drive can be as high as 200-220MB/sec.
Certain 15K drives, can manage 300MB/sec, but I don't
own any of those :-)

To do 90GB at 65MB/sec takes 90000/65 = about half an hour :-)
To Robocopy a similar amount, would take longer (allowing
for random access head movement on source). Intelligent Cloning
should be mostly sequential (the software can compute a map
of what sectors must be copied, to make a complete imaging
of the info). You can use Process Monitor from Sysinternals,
if you need to keep a log of how it does the actual operations.
The WriteFile size and starting LBA recorded in Process Monitor,
can help you understand how software copies stuff.

Paul

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