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GeneralRe: Windows updates - estimated time Pin
StarNamer@work13-Sep-23 6:17
professionalStarNamer@work13-Sep-23 6:17 
GeneralRe: Windows updates - estimated time Pin
DerekT-P13-Sep-23 22:07
professionalDerekT-P13-Sep-23 22:07 
GeneralRe: Windows updates - estimated time Pin
Mark Starr14-Sep-23 4:45
professionalMark Starr14-Sep-23 4:45 
GeneralRe: Windows updates - estimated time Pin
dandy7213-Sep-23 3:51
dandy7213-Sep-23 3:51 
GeneralRe: Windows updates - estimated time Pin
snorkie13-Sep-23 4:06
professionalsnorkie13-Sep-23 4:06 
GeneralRe: Windows updates - estimated time Pin
jschell13-Sep-23 5:08
jschell13-Sep-23 5:08 
GeneralRe: Windows updates - estimated time Pin
trønderen13-Sep-23 5:51
trønderen13-Sep-23 5:51 
GeneralRe: Windows updates - estimated time Pin
trønderen13-Sep-23 5:22
trønderen13-Sep-23 5:22 
snorkie wrote:
Conversely, I would argue this is a hard problem to solve.
To make an exact estimate is impossible, especially when the machine is available for other use in parallel with e.g. a file copy operation.

If you have received a time estimate, and then start an operation that hogs all system resources for half an hour, you know that the estimate will be wrong. The problem is that if you do not start anything, the estimate still jumps up and down by a factor of 5, maybe 10, maybe 30. That is what makes little sense!

For the initial estimate, the number of files to be opened for read and for write is known, and on which devices. The amount of data in each file is known. The PC should know from earlier experience how much time a file open typically takes on the various devices. It should know from earlier experience the typical transfer speed from the source device, and to the destination device, and go for the lower in the estimate calculations. Also, the estimator should pay some attention to the size of disk buffers: Typically, transfer speeds are high until a read cache is empty, or a write cache is full; after that it drops. This can be learned from experience. So the initial estimate should be close to the typical time from earlier experience in the same installation.

The problem seems to be that if the measured transfer speed deviates from the typical speed for half a second, e.g. because some application flushed a thousand modified disk pages, then all earlier estimates seems to be thrown away completely. The estimate is not slightly adjusted, but entirely recalculated based on that half second. If the expected total time is 500 seconds and for 0.5 seconds the measured transfer speed is almost down to zero, the next estimate should be based on a transfer speed 999/1000 of the "typical" one. Similar for file open and other operations.

After completing one such operation, the actual average time for file open/close and transfer speed should be used to adjust - not replace - the "typical" times for that device stored in the registry, e.g. like new typical = old*0.9 + last*0.1. So if you more or less always run other applications in parallel with the copy, the typical value may slowly crawl upwards to a "correct" value for your machine. If the initial typical value was based on your old SATA flash disk, recently replaced with a much faster M.2 disk, the typical timing values where that disk is involved may slowly crawl down to a lower, fairly stable value.

For the Windows update, there is also a processing element. MS should know that on this model PC, this processing step takes x seconds - but on one specific PC, in all previous updates, experience shows that the real time used for processing steps has on the average taken twice as long as on the model PC. So in the estimates, we assume that the step will take 2x seconds.

For both file copy and e.g. updates, there often seems to be some sort of final "cleanup" actions, much more than just closing files. (I hate it when the progress bar sits at "99% complete" for as long as the completed 99%!) Typical cleanup times after various classes of operations may be measured as well, stored in the registry and used as expected values in future operations of the same class.

If you base all such estimates on earlier experiences from the very same machine, there is no way that they could be off by a factor of 5, or 30. Or that they would jump wildly up and down. If you have updated your hardware, or if you put a heavy load (or remove a heavy load that was there earlier), you will see estimates that are somewhat off, for a while. But no crazy jumping up and down.

I refuse to believe that Windows base its estimates on earlier experience on the same PC. I refuse to believe that they let a brief, temporary deviation from typical performance have an effect on the estimate proportional to the duration of deviating measurement. If they did, there is no possible explanation why the estimates are bouncing wildly and sometimes off by a huge factor with no meaningful explanation.

MS apparently concluded: Making an exact estimate is so hard that we give up. We won't even try to make any reasonably close estimate.
GeneralRe: Windows updates - estimated time Pin
Gary Wheeler13-Sep-23 5:01
Gary Wheeler13-Sep-23 5:01 
GeneralRe: Windows updates - estimated time Pin
Gerry Schmitz13-Sep-23 6:31
mveGerry Schmitz13-Sep-23 6:31 
GeneralRe: Windows updates - estimated time Pin
MikeCO1014-Sep-23 2:39
MikeCO1014-Sep-23 2:39 
GeneralRe: Windows updates - estimated time Pin
trønderen14-Sep-23 6:10
trønderen14-Sep-23 6:10 
GeneralRe: Windows updates - estimated time Pin
sasadler14-Sep-23 6:10
sasadler14-Sep-23 6:10 
GeneralRe: Windows updates - estimated time Pin
OldDBA14-Sep-23 11:56
OldDBA14-Sep-23 11:56 
GeneralWSO CCC OTD 2023-9-13 Pin
OriginalGriff12-Sep-23 21:35
mveOriginalGriff12-Sep-23 21:35 
GeneralRe: WSO CCC OTD 2023-9-13 Pin
pkfox12-Sep-23 22:06
professionalpkfox12-Sep-23 22:06 
GeneralRe: WSO CCC OTD 2023-9-13 Pin
Rich Leyshon12-Sep-23 22:43
Rich Leyshon12-Sep-23 22:43 
GeneralRe: WSO CCC OTD 2023-9-13 Pin
OriginalGriff12-Sep-23 22:45
mveOriginalGriff12-Sep-23 22:45 
GeneralRe: WSO CCC OTD 2023-9-13 Pin
DerekT-P12-Sep-23 23:08
professionalDerekT-P12-Sep-23 23:08 
GeneralRe: WSO CCC OTD 2023-9-13 - we have a winner! Pin
OriginalGriff12-Sep-23 23:47
mveOriginalGriff12-Sep-23 23:47 
Generalstrange noggin bumps from face-palming my laptop Pin
BillWoodruff12-Sep-23 19:10
professionalBillWoodruff12-Sep-23 19:10 
GeneralRe: strange noggin bumps from face-palming my laptop Pin
jmaida12-Sep-23 20:04
jmaida12-Sep-23 20:04 
GeneralRe: strange noggin bumps from face-palming my laptop Pin
BillWoodruff12-Sep-23 23:32
professionalBillWoodruff12-Sep-23 23:32 
GeneralRe: strange noggin bumps from face-palming my laptop Pin
jmaida12-Sep-23 20:06
jmaida12-Sep-23 20:06 
GeneralRe: strange noggin bumps from face-palming my laptop Pin
BernardIE531713-Sep-23 1:28
BernardIE531713-Sep-23 1:28 

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