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Why do computers want us to eject USB drives?

Do I really need to eject USB Drives after I copy or move something from ? Ever wonder why my computer warns me about ejecting those USB drives before I remove them? Do you recommend ejecting all my drives anyway?

 

 

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Question added by Ghada Eweda , Medical sales hospital representative , Pfizer pharmaceutical Plc.
Date Posted: 2016/04/05
Ghada Eweda
by Ghada Eweda , Medical sales hospital representative , Pfizer pharmaceutical Plc.

Some of my computers like my Mac are always warning me about disconnecting flash drives without ejecting, while Windows doesn't seem to have a problem—in fact, my external USB drive doesn't even have an eject option. I wonder does this mean it's safe and  I try to know when I actually need to eject a drive. This is kind of question  has a short answer and a long answer.

The short answer :

 We  should probably always eject a drive before removing it, even if the context menu doesn't have an eject option. Mac and Linux will always provide us a way to eject a drive, but sometimes Windows doesn't have an obvious "Eject" button for certain drives. So, on Windows, I try to click the "Safely Remove Hardware" icon in the system tray, choose your drive from the list, and then remove it once it notifies you of its safe removal.

Now, the long answer:

In Windows, you can sometimes remove a flash drive without ejecting. Here's a bit more information on how computers deal with USB drives.

Why Computers Want You to Eject Drives

Do I Really Need to Eject USB Drives Before Removing Them?

Obviously, yanking out a drive while it's being written to could corrupt the data. However, even if the drive isn't actively being written to, you could still corrupt the data. By default, most operating systems use what's called write caching to get better performance out of your computer. When you write a file to another drive—like a flash drive—the OS waits to actually perform those actions until it has a number of requests to fulfill, and then it fulfills them all at once (this is more common when writing small files). When you hit that eject button, it tells your OS to flush the cache—that is, make sure all pending actions have been performed—so you can safely unplug the drive without any data corruption.

Why Windows Doesn't Bug You to Do It

Do I Really Need to Eject USB Drives Before Removing Them?

Mac and Linux use write caching on pretty much all drives, and will let you eject any drive through your file manager. Windows, however, is a bit more mysterious on this front. It actually disables this write cache feature for drives it sees as "removable", because it knows people are likely to yank them out without ejecting (though you can still eject them by right-clicking on them and pressing "Eject"). As such, disabling this feature on removable drives decreases the chance of data corruption. It keeps the cache enabled on non-removable drives, though—and sometimes it recognizes external USB drives asnot removable, which is why your USB drive doesn't have an eject button. Paradoxically, it's also why you need to eject that drive: since Windows doesn't see it as removable, it's enabled the write cache for it, increasing the chance of data corruption.

You can edit the write cache settings for any drive from the Device Manager. Just expand the Disk Drives section, right click on the drive you want to edit, and hit Properties. Go to the Policies tab, and click the "Quick Removal" radio button to disable the cache (or click "Better Performance" to enable the write cache).

Why You Should Probably Manually Eject All Your USB Drives Anyway

Do I Really Need to Eject USB Drives Before Removing Them?

So, unlike OS X and Linux, Windows has a few precautions in place for preventing data loss. However, the write cache isn't the only thing that can cause data loss. Have you ever tried to eject a drive and gotten a "file is in use" error? Sometimes there's something going on in the background you don't know about, or sometimes a program is just being silly and has still locked a file on the drive even if it isn't using it. If you were to yank it out during one of these situations, you could still cause data loss. Ejecting it will warn you of the situation, and let you close the program in question (or use something like previously mentioned Unlocker to unlock the in-use file).

  Unlocker Deletes Locked Files, Now Works for-bit Windows

Windows only: Freeware system utility Unlocker deletes, moves, or copies locked files that you…Read more

In the end, there's no reason not to eject your drives, and doing so will ensure your data is uber-safe. Windows users may be less likely to experience issues due to the way Windows handles removable drives, but they aren't% immune. Ejecting the drive is a great habit to get into, since without it, you wouldn't always know if it were safe to remove or not.

Omar Shammakh
by Omar Shammakh , IT Manager , Vibes Offices

When you plug in a USB drive, you give your PC free rein to write and read data from it; some of which is cached. Caching occurs by not writing information immediately to the USB device, and instead keeping it in your PC’s memory (RAM). If you were to yank the USB drive out of your PC before this information is written, or while its being written, you’ll end up with a corrupted file. However, Windows automatically disables caching on USB devices, unless you specifically say that you want it enabled. For the most part you don’t have to click the ‘Safely Remove Hardware’ button, if you aren’t writing or reading anything from the device. Its there simply as an extra level of security preventing you from destroying your own files. Doing so causes the files to close “gracefully”, preserving data, pointers and file size indicators. When writing to disk the computer doesn’t always “flush” a buffer and only part of the data may have been written. Using the proper procedure will assure that the data and pointers are in good shape.

Giovanni Taborada
by Giovanni Taborada , Network Engineer , Amwaj

Properly ejecting your pen drives or any other external drives or parts, is highly recommended. Because, if some other application/s still uses or accessing your drives (e.g. copying, moving, deleting, scan by anti-virus)  and you force to remove it. It may damage your drives, specially external HDD is highly sensitive. Sudden loss of power supply, the pin inside will not turn into home base. This will damage your external HDD and cannot be accessible anymore.  Hope this will help.

Elke Woofter
by Elke Woofter , Project Assistant , American Technical Associates

https://www.reddit.com/r/explainlikeimfive/comments/2u1jfb/eli5why_do_computers_insist_that_we_safely_eject/

"Computers use what's called a 'write cache', which basically means that when something needs to be written, it isn't immediately written, but the computer waits a bit to see if more things need to be written, etc. Sort of like a bus waiting for more passengers before it departs. If you remove the USB too soon after you wrote something there, there is a chance that what you wanted to write is in the cache and hasn't been transferred yet."

georgei assi
by georgei assi , مدير حسابات , المجموعة السورية

I apologize, because I admit that my experience is weak in this area

abdul khayyum bashir ahmed
by abdul khayyum bashir ahmed , Human Resources Administrator , Al Diwan Al Amiri

If your drive (or device) connects using the  USB Mass Storage protocol then it should ideally be ejected. Although, as we’ll see, it differs slightly depending on whether you’re using Mac or Windows.

This applies even if you’re not actually using the device at the time.

The reason is because operating systems use a process called write caching. The operating system doesn’t always write a file to a drive immediately, but instead caches it and waits until it has multiple write operations to complete.

Doing these all at once improves performance, but if the cache is still full when you remove the drive, your data will become corrupted. Clicking the Eject button causes the cache to be emptied and any remaining data to be written to the drive.

That’s the reason why there’s often a delay of several seconds between ejecting the drive and being notified that it’s safe to remove it.

There are also potential issues with the abrupt removal of the power supply from a flash drive. Flash memory is susceptible to this, and it can cause parts of the drive to become corrupt.

 

Mohammed Amin Petiwala
by Mohammed Amin Petiwala , CFO , Osool Poultry SAOC

experts have given good explanatory answers

Adam Ahmed
by Adam Ahmed , IT & Web Developer , Freelance

Basm allah alrahman alrahim

 

USB is Storage Device With Filesystem exactly like any filesystem ( fat32 , NTFS ..etc ) , this filesystem must be recognized by the Operating system , So when you Enter USB ( mount ) it became a part of the computer , like any other part ( like hard disk , ram , DVD ..etc ) , what will happen if any file was transferred or deleted while ejecting by force , there is a table at any filesystem this table contain information about any file at the storage partition ( e.g file location and size and a lot of other information ) , what will happen is that you may killing the process before done (i.e deleted or transferred file ) , the filesystem table will not recognize that the process did not finish ( that will result a corrupted table ) , its a very complicated process , operating system vendors try to make solution for that ( that's way most of the time nothing happens when ejecting by force , but that's not 100% right so problems will appear sooner or later)

Look how many problems may appear if you don't eject USB

 

Note

The Table at NTFS called master file table ( MFT )

 

د Waleed
by د Waleed , Management - Leadership-Business Administration-HR&Training-Customer Service/Retention -Call Center , Multi Companies Categories: Auditing -Trade -Customer service -HR-IT&Internet -Training&Consultation

Briefly because it is the safest way to keep your used files safe and to make sure that you properly finished working from/to USB or external drive !

 

Thank You

Angelo Gonzales
by Angelo Gonzales , Encoder , BFL Group LLC

Before you remove the USB drive or external drive etc. you safety eject it first because if you did not do that your copy or transfer file on that drive maybe it will lose or your drive will have a virus cause of your not doing the right ejecting of the drive.

Mohammad Iqbal Abubaker
by Mohammad Iqbal Abubaker , Jahaca Pty Ltd - Accounts Administrator , Jahaca Pty Ltd - Accounts Administrator

I AGREE WITH THE Answer added by: Ghada Eweda  Medical sales hospital representative 30 days ago

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