Do you want to know how to configure Windows so that you don’t have to use the Safely Remove Hardware notification icon, to unplug external USB devices such as flash memory sticks or hard disk drives? Is it safe to disable it and what is the performance impact of this choice? The answers to all these questions are covered in this article.
When using an USB flash memory stick or an external hard disk among many computers, it happens rather often that, when you plug that device into a computer, you are informed about possible problems with some files on it. That’s because you might have pulled it out without using the Safely Remove Hardware option.
Most times you encounter this prompt, there’s nothing wrong with the files on the drive and you can use them without issues. However, it can happen that some files were indeed corrupted. In that case, using the Scan and fix option solves your problems.
This is fine and dandy but, what can you do to lower the number of such prompts? And, can you unplug the USB device (memory stick or external hard drive) without having to use the Safely Remove Hardware notification icon?
The Solution: Enable the Quick Removal of USB Devices/Disable Write Caching
First, open the Device Manager. You can do it by searching for the word device in the Start Menu search box. You can find a good guide with more ways to launch it, here: Find Missing Drivers & Hidden Devices with Device Manager.
Once the Device Manager window is open, go to the list of Disk drives and expand it. There you can see your computer’s internal hard disk drive(s) plus the external USB devices plugged in. Such devices will always have USB in their name.
Double click on the device for which you want to quit using the Safely Remove Hardware option. In its Properties window, go to the Policies tab. There you will find two options: Quick removal and Better performance.
If Better performance is checked, it means that, while you might get better performance in some write scenarios, you must use the Safely Remove Hardware notification icon to disconnect the USB device.
Select Quick removal and click OK.
Now write caching is disabled for the selected USB drive (memory stick or external hard disk). This means that, once you are done working with it, you can unplug it directly. You won’t have any problems.
However, if you unplug the drive in the middle of writing some files to it, you will most probably encounter the "scan and fix" prompt shown at the beginning of this article.
Don’t hesitate to repeat the procedure for all the devices on which you want to disable using the Safely Remove Hardware notification icon. Windows remembers your setting even if, later on, you plug that device into other USB slots.
What is the Performance Impact? - A Quick Benchmark
At least in theory, there should be some performance impact for not using write caching in Windows, for external USB devices. I wanted to test this hypothesis and learn more about the performance impact.
For my tests II used three devices: a Corsair Voyager GT 16 GB USB flash memory stick, a generic noname 2 GB USB Flash Memory Stick I received at some press event and an external 1TB USB hard disk drive from LaCie.
I formatted the devices and ran CrystalDiskMark when the option Better Performance was used (write caching turned on). Then, I checked the option Quick Removal, which disables write caching and repeated the test. Then, I compared the results.
The measurements performed by CrystalDiskMark are the following: sequential read & write, random read & write - in 512KB blocks, random read & write - in 4KB block with a queue depth 1 and 32. More about how this application works, can be found here.
When write caching (Better performance) was turned on for my Corsair flash memory stick, these were the results I obtained:
When write caching was turned off (Quick Removal on), I obtained very similar results. There was a slight deterioration in write performance (less than 5%) but small enough not to be noticed. Surprisingly, the read performance improved with approximately 1% when Quick Removal was on.
What about my generic USB memory stick? It was never a fast performer. These were the results with write caching turned on.
The performance impact of not using write caching was even smaller than for the Corsair memory stick - up to 1%. Certain read operations were done slightly faster but not all. There was a gain of less than 0.5%.
Last but not least, let’s see how my external LaCie USB hard disk drive fared. When write caching was enabled, these were the results I obtained:
With write caching disabled, the write performance was lower with less than 1%, while the read performance improved by a small degree - up to 2% for certain read operations.
The changes are not spectacular, are they?
The Conclusion - It is Safe Not to Use Safely Remove Hardware
Looking at these results, there is only one conclusion: it is OK to disable the use of the Safely Remove Hardware notification icon. This means disabling write caching for your external USB devices and using the Quick Removal setting instead of Better performance. The performance levels are almost identical between the two options and you earn the comfort of making less clicks to remove external USB devices.