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A comment on How did MS-DOS decide on two seconds to keep the floppy disk cache valid?.

Re:How did MS-DOS decide on two seconds to keep the floppy d... by coliveira on Tuesday September 24, 2019 @05:04PM (#21064616)
Two seconds is the time it takes in Formula 1 for mechanics to lift a car, change four tires, and put the car back in movement. It is difficult to believe that you cannot swap flop drives in less than that time.
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Re:How did MS-DOS decide on two seconds to keep the floppy d... by aidenn0 on Tuesday September 24, 2019 @05:54PM (#21065029)
I can do a 3.5" in less than 2s, but I assume they were testing with 5.25"

Those usually had a lever rather than a button so it was a 4 step process rather than a 3 step process:

3.5":

- Press button

- Remove Disk

- Insert Disk

5.25"

- Turn lever

- Remove Disk

- Insert Disk

- Turn lever

Add to this the fact that 5.25" floppies were less rigid, and expensive enough that you don't want to damage, and it takes a lot longer.

That being said, I think I did get down to just barely under 2s when I was restoring my hard disk from 97 5.25" floppies after getting a virus (the backup program being used bypassed DOS's system calls for accessing the disk, and polled multiple times per second so you didn't even need to press a key after inserting the disk).

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Re:How did MS-DOS decide on two seconds to keep the floppy d... by skykooler on Tuesday September 24, 2019 @05:07PM (#21064647)
Doing it F1 style, you'd have one person take out the first floppy while a second person inserts the second floppy.
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Re:How did MS-DOS decide on two seconds to keep the floppy d... by zeeZ on Tuesday September 24, 2019 @05:14PM (#21064711)
You need a third person to push the button that ejects the floppy.
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Re:How did MS-DOS decide on two seconds to keep the floppy d... by pmccarren on Tuesday September 24, 2019 @05:23PM (#21064773)
And you'd need a fourth person to push the floppy in.
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Re:How did MS-DOS decide on two seconds to keep the floppy d... by hdfbdtbcdg on Tuesday September 24, 2019 @05:22PM (#21064769)
And a fourth playing the game.
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