totally reliability or speed or?

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Re: totally reliability or speed or?

Postby DrTeeth » Sun Nov 29, 2015 1:36 pm

On Sat, 28 Nov 2015 09:16:32 PST, just as I was about to take a herb,
"TeraByte Support" disturbed my
reverie and wrote:

>If people are interested, we can implement a old method of detecting changes
>for both backup and restore that can be much faster but it is more
>unreliable.

I would generally go for reliability each time.

Is there any quantitative data for both the methods?

If the less reliable method were much faster I may be tempted. After
all, I do not use byte-for-byte validation.
--
Cheers,

DrT

"If you want to find out what is wrong
with democracy, spend five minutes with
the average voter." - Winston Churchill
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Re: totally reliability or speed or?

Postby TeraByte Support » Sun Nov 29, 2015 8:11 pm

Reduced to the simplest form, if there is data corruption, using metadata is
not enough to guarantee the corruption will be removed on a restore.

Using metadata would be fine if there is no data corruption. It's just the
nature of the beast, even if file system problems caused data corruption,
chkdsk may fix up or delete the file in question (modifying the dates (and
perhaps size) on the metadata), but other files that are fine as far as
chkdsk is concerned may still be corrupt in the data itself.







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Re: totally reliability or speed or?

Postby VanBuran » Wed Dec 02, 2015 2:24 am

Reliability, for me, is more important than speed :D
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Re: totally reliability or speed or?

Postby DrTeeth » Wed Dec 02, 2015 10:41 am

On Wed, 2 Dec 2015 01:24:54 PST, just as I was about to take a herb,
VanBuran disturbed my reverie and wrote:

>Reliability, for me, is more important than speed

As a result of this thread, the quoted post, the fact that I leave my
PC backing up at the end of the day and having IfW shutting down my
PC; have decided to use byte-for-byte verification.
--
Cheers,

DrT

"If you want to find out what is wrong
with democracy, spend five minutes with
the average voter." - Winston Churchill
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Re: totally reliability or speed or?

Postby B00ze » Wed Dec 16, 2015 7:19 pm

TeraByte Support wrote:

> If people are interested, we can implement a old method of detecting
> changes for both backup and restore that can be much faster but it is more
> unreliable. It may be "good enough" for clean file systems but overall,
> it's NOT "totally reliable".

I'm with most people, I want reliability over speed. There's nothing more frustrating than to restore an image of the boot partition and discover that Windows Update no longer works, that the iconcache is corrupted, etc.

> While the write tracking method recently added is not totally reliable,
> it's a step above metadata.

What do you mean here, you got me worried. Image For Windows uses this "not totally reliable" method for incremental images? How unreliable is it?

Thanks.
Best Regards,
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Re: totally reliability or speed or?

Postby TeraByte Support » Wed Dec 16, 2015 11:58 pm


> While the write tracking method recently added is not totally reliable,
> it's a step above metadata.

What do you mean here, you got me worried. Image For Windows uses this "not
totally reliable" method for incremental images? How unreliable is it?

"write tracking" is an option you can enable in 2.98

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Re: totally reliability or speed or?

Postby tas3086 » Thu Dec 17, 2015 4:38 pm

Are you saying, that to be absolutely totally reliable and backing up a live partition such as the Windows partition, that your should use a method like IFL, IFD, or the WinRE version of IFW? Thus, use a method that does not use the partition that you are trying to back up?

The TRACK WRITES definition was not very clear. It was clear that using it would be less reliable, but it was not clear that not using it and relying on Phylock/VSS would be absolutely reliable.
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Re: totally reliability or speed or?

Postby B00ze » Thu Dec 17, 2015 4:43 pm

Ah ah, it's a method for making Live backups; good, I don't use that - I've been burned before, I only do offline. Thanks.
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Re: totally reliability or speed or?

Postby TeraByte Support » Thu Dec 17, 2015 6:31 pm

Track Writes can theoretically miss changes if they are requested by a
driver closer to the drive than phylock itself and when using that it will
only compare those sectors which are known to have changed. When not using
that option it checks all the sectors in use for changes.



"tas3086" wrote in message news:10710@public.image...

Are you saying, that to be absolutely totally reliable and backing up a live
partition such as the Windows partition, that your should use a method like
IFL, IFD, or the WinRE version of IFW? Thus, use a method that does not use
the partition that you are trying to back up?

The TRACK WRITES definition was not very clear. It was clear that using it
would be less reliable, but it was not clear that not using it and relying
on Phylock/VSS would be absolutely reliable.

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Re: totally reliability or speed or?

Postby Brian K » Thu Dec 17, 2015 7:14 pm

B00ze wrote:
> Live backups; good, I don't use that - I've
> been burned before, I only do offline.

I've been using IFW (Live backups) for almost 10 years without an issue. What burned you?
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