Why does it take so much longer to download data on devices than to delete it?



Why is it that it takes my phone almost an hour to download 6GB worth of data for an app, but upon deleting the app, it only requires less than 10 seconds to wipe all the data in the app from my phone? By deleting the app from the phone, I mean deleting the app from the home page. Thanks in advance!

In: Technology

>it only requires less than 10 seconds to wipe all the data in the app from my phone?

This is not what happens.
A simple deletion is instant because your operating system does not physically move around or remove data. It simply assigns the existing data a new path or removes an existing one. Think of it as changing labels in a warehouse – instead of moving a box from row 1 to row 4, you simply look at row 1 and say “this is now row 4”.
In that case it’s “this row is empty”.

Deleting data on a computer or phone only means marking the space it takes up as available for re-use. That’s rather fast since the data is not “wiped clean” or otherwise destroyed. It merely becomes unseen by you. Downloading an app or files, however can only proceed as fast as your cellular or wifi network can deliver the data so it generally takes much longer.

“Deleting” a file doesn’t really delete it; the phone just says “hey, this whole big chunk of storage space isn’t used anymore”. Then the next time it needs to look for a place to store data, it might use some of that big “deleted” block.

Pointing at something and saying “That’s not used. I can re-use it now.” takes a second. Downloading 6 gigs takes many, many seconds.

* Downloading = putting everything in a specific place in memory byte-by-byte, and then adding it to the list of things in memory.
* Deleting = removing it from the list.
* Deleting doesn’t remove it from memory byte-by-byte.
* But by removing it from the list, the device knows it can just write over the old data with new data when it needs to.

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