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File Copy time estimates

Posted: Sun Nov 27, 2016 2:11 am
by middings
In the topic [url=https://www.reactos.org/forum/viewtopic.php?f=2&t=16054&p=124229#p124229]ReactOS kernel status[/url], PurpleGurl wrote:Yes, the percentages would be no more accurate than Windows's estimated file transfer times. 1 minute, 3 days, 2 hours, 30 seconds, done.
xkcd Estimation

Will ReactOS be bug-for-bug compatible with Windows's estimated file transfer times? Knowing if there is time to get a cup of coffee depends on this. :lol:

Why does the copy dialog give such horrible estimates? Raymond Chen of Microsoft answers.
(Bonus blog comments by MS's Larry Osterman.)

Choosing the information a file copy dialog shows to the user is surprisingly difficult. Raymond Chen again,
Why doesn’t the Windows Vista copy progress dialog show the names of the files being copied?
and Why doesn’t the Windows Vista copy progress dialog show the names of the files being copied?, redux

Re: File Copy time estimates

Posted: Sun Nov 27, 2016 7:15 am
by PurpleGurl
I imagine we could do better without hurting things, since I don't think this is an essential bug. For reference, Windows 7 has the WEI index to give a rough idea of how well the PC performs. Now, what if there was a way to store estimates and average PC performance in advance and take that into account, maybe adjust it with time? Now, the problem is that there are too many variables. The amount of available memory would determine the size of buffers used, CPU performance and current load would affect copying speed, and hard drive usage would also need to be taken into account. The problem is that these cannot be predicted, and if you measure them each time, you make things more complicated than necessary and may slow things more.

Re: File Copy time estimates

Posted: Mon Nov 28, 2016 10:13 pm
by Black_Fox
As the network bandwidth increases and many consumers (who don't want to understand the complexity of giving a good prediction) are switching from HDDs to SSDs, I think this problem is not as bad as it was earlier.
BTW, thanks for linking The Old New Thing, luckily I've read only about three or four of the blogposts, I still have some part of the evening left :D

Re: File Copy time estimates

Posted: Sat Dec 03, 2016 10:24 am
by forart
I strongly suggest to "learn" copy-mechanism from FastCopy: https://ipmsg.org/tools/fastcopy.html.en

Re: File Copy time estimates

Posted: Sat Dec 03, 2016 7:33 pm
by Swyter
Just by using a rolling window average to smooth out bytes/sec the estimation would look a bit more realistic.
There are fancier things like Kalman filters that can provide even better results. Shouldn't be that difficult.


[ external image ]

See how the raw spikes get averaged.