On Sun, Apr 26, 2009 at 12:10:35PM -0400, Matthew Miller scripsit: > On Thu, Apr 23, 2009 at 09:12:25PM +0100, Bob W wrote: > > I should think the difference is fairly minimal. To delete all, the system > > probably just sets a 'deleted' status for each file entry in the FAT, > > whereas to format the card I expect it simply writes a new FAT. In either > > case I'd be surprised if there was any great difference in the number of > > I/Os. > > On my K10D, it's significantly slower to delete-all.
Delete all = couple hundred to a couple thousand operations on the FAT, depending on the number of files on the card. Especially in the camera, it's probably a case of "open FAT, delete file #1, write FAT back out, close FAT, open FAT, delete file #2, ....". Format = replace FAT with empty FAT, in a single operation. So format is going to be quicker in-camera if the card has any significant number of files on it. rm -rf /media/dcim/100_0426 with the card in a reader and mounted by linux, on the other hand, is very fast. -- Graydon -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
