XL Delete can take a long time to securely delete large files because it actually overwrites every byte of the file several times. So if you are trying to delete a 10 MB file, XL Delete will write 10 MB worth of data for each overwrite pass. If you choose a wipe method such as DoD-7, XL Delete will overwrite the file 7 times so the total amount of data written would be 70 MB. If you were to securely delete a 1 GIG file using the same method, you would write a total of 7 GIG's of data to securely delete it. Note that the data is overwriting the original file so you will not actually see extra data written to your hard drive. This is how all secure delete tools work.
Is there something I can do to make it go faster?
Yes, there are two things you can do to make a deletion go faster.
- If you are not deleting sensitive data, consider using the DoD-3 method which will only overwrite the file 3 times. Remember that the more wipes equals better security.
- Increase the buffer size in the Settings dialog when deleting large files. The buffer size is measured in bytes. The default buffer is set to 2kb (2048 bytes) but you can use a much larger buffer for big files such as 5 MB (5242880 bytes). Remember to lower the buffer if you do not delete large files often as a lower buffer makes the deletion process much faster for smaller files. You can experiment by trying different buffer sizes to see which one works better for you. Results will vary depending on the amount of RAM and type of hard drive you use.
XL Delete has an "auto buffer" feature which will make the program automatically select the best buffer size to use for every file. This can speed up the deletion time by as much as 50%. This feature is enabled by default. You can choose to use your own buffer size by unchecking this option in the settings dialog and entering a buffer size.