Can mounting a usb flash drive with the sync option damage it ?

electronpusher · 03-03-2008, 03:22 PM

I came across something on the internet that said that the sync option was on by default on some Linux systems and that this would damage flash drives using a VFAT file system by repeatedly writing to the FAT. It also said that even though the man page said that the default was to NOT mount with sync some systems do anyway. Should I be concerned? How can I conclusively verify that this is NOT happening? I ran mount with out parameters and neither async or sync was listed. I am using Ubuntu Dapper Drake. Thanks a LOT for any help anyone may be able to render. I'm worried.

ilikejam · 03-03-2008, 05:24 PM

Hi.

Don't worry about it. The sync option flushes any writes to disk immediately instead of caching, so you'll tend to get more writes if you're doing a lot of file manipulations which, over time, will wear out the flash memory on the drive. Fortunately, though, the write cycle life of most recent flash is in the 100's of thousands of operations before you should see any effects. If it's just an external storage key for moving files between machines, then it'll probably outlive you whether sync is switched on or not.

It's probably actually safer to have sync on, as there's less likely to be any corruption should you pull the drive out without unmounting it.

Dave

David the H. · 03-04-2008, 10:04 AM

More important I think is to add the noatime (or perhaps relatime) and nodiratime mount options, which prevent the system from updating the access times of files and directories when they are only being read. This can save a lot of write/erase cycles and increase the active life of flash memory; and possibly improve performance as well. It's probably a good idea to use it on all of your drives, actually.

electronpusher · 03-04-2008, 12:27 PM

Your posts were timely and very helpful..... I feel a WHOLE lot better!

electronpusher · 03-04-2008, 12:46 PM

I think I'm going to do as David the H suggests and mount my flash drives with the options he suggested. Would it be best to do this from the command line? I have no problems with that. I guess I would have to put an entry in fstab? What should I put? Does anyone have any suggestions? Thanks again!