Julian Foad wrote: > I thought it was the other way around: that most Linux filesystems (by > which I mean ext2) and NTFS had 1K or 0.5K blocks, and that Windows > FAT filesystems had big (generally 4K to 16K) blocks.
Nope, 4k. The underlying disks have 512 byte blocks (all IDE and most SCSI, at least), but the OS doesn't cut things that fine. The 4k block size matches the processor page size on x86 and most other processors, so it makes things like swap and mmap'ed I/O simpler to implement. You can see this for yourself pretty easily (this is ext3; I'd be curious to see what the results are on other filesystems): # Make a scratch area mkdir foo cd foo # Make 100 empty files for i in 0 1 2 3 4 5 6 7 8 9; do for j in 0 1 2 3 4 5 6 7 8 9; do touch $i$j done done # Note that no space is taken up by the empty files, only 4k for the # directory itself cd .. du -s foo # Now append one byte to each of them cd foo for i in *; do echo "" > $i done # Note that the directory now contains 404k -- 4k per file cd .. du -s foo -- Andrew J. Ross NextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com "Men go crazy in conflagrations. They only get better one by one." - Sting (misquoted) _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
