Acronis Disk Director 11 Advanced Workstation - User Guide - Manual (Page 48)

48 Copyright © Acronis, Inc., 2000-2010
4. Click OK to run the volume check. If the volume contains a very large number of files—for
example, millions—the check can take a long time to complete. The results of the operation will
be displayed in a separate window.
Note: If the volume is in use, the tool can only check it for errors, but cannot repair them. The checking and
fixing of errors on this volume will be performed the next time you restart the system.
6.20 Defragmenting a volume
This operation is enabled in Windows operating systems, and is disabled under bootable media.
Defragmentation increases the system performance by consolidating fragmented files on a volume.
Fragmentation occurs when the operating system cannot allocate enough contiguous space to store
a complete file as a unit and thus, writes different pieces of a file in gaps between other files. The
defragmentation rearranges pieces of each file as close together and contiguously as possible,
minimizing the time required to access it.
Acronis Disk Director does not perform defragmentation itself, rather it launches the Disk
Defragmenter tool (Defrag.exe) included in Windows operating system.
To defragment a volume
1. Right click the volume you need to defragment, and then click Defragment.
2. In the Defragmentation window, click OK to start defragmenting the volume.
Depending on the amount of fragmented files, the defragmentation may take a long time to
complete. The results will be displayed in a separate window.
6.21 Changing a cluster size
Changing a cluster size of a volume affects the amount of free/used disk space.
Smaller cluster sizes allow for more efficient storage of smaller files by reducing the amount of
wasted disk space. Furthermore, larger files may become more fragmented across the volume,
increasing the amount of time that is needed to access them.
Bigger cluster sizes improve performance by decreasing the time to access to larger files. However,
having a bigger cluster size wastes disk space if the typical size of the files stored on the volume is
smaller than the cluster size.
To change cluster size
1. Right-click the volume whose cluster size you need to change, and then click Change cluster size.
2. Select the required cluster size from the list. The default cluster size is marked in the list as
(default). The default cluster size depends on the volume size and the type of the file system. For
example, the default cluster size for up to 2-TB NTFS volumes is 4 KB.
Important: The program does not allow you to select a particular cluster size if, the free volume space will
decrease to the point where the data will not fit on the volume.
Some programs do not work correctly with volumes whose file systems have big cluster sizes, such as a
cluster size of 64 KB in the FAT16 and FAT32 file systems, and cluster sizes of 8 KB through 64 KB in the
NTFS file system. For example, these programs may incorrectly calculate the total and available space on
such volumes. Acronis Disk Director displays warning messages, when you select such cluster sizes.
3. Click OK to add the pending cluster size changing operation.