Zoyd W.

Both NTFS and Ext3 log date and time of last access for all files and directories.

This is quite useful for some applications (mutt, backup apps, forensic analysis, optimizing defragmenters that move frequently accessed files to the faster cylinders on the hard disk, etc.). However this incurs in a heavy overhead because each file read operation carries an additional seek and write. Whenever many short files are read, a serious performance loss ensues.

It is recommended to disable these mechanisms when the above mentioned applications aren't needed (e.g., a host where no forensic analysis will be required, or a virtualized Windows guest where no file block placement optimization strategy would be useful) .

On Linux: add the noatime option to the mount options in /etc/fstab (only for filesystems that support it).

On Windows XP: run the command line "fsutil behavior set disablelastaccess 1", which writes a REG_DWORD with value 1 on variable NtfsDisableLastAccessUpdate at HKLM\SYSTEM\CurrentControlSet\Control\FileSystem .

Labels: ext3, fsutil, noatime, ntfs