You can find a brief description on the
share page.
The installation of CompactVD must be done on the host-related part. Just
drag a vdi or vmdk disk image into the main window.
CompactVD is a utility to optimize the size of dynamic disk images, based on the bitmap allocation tables of known file systems. You can check if there is wasted space in a dynamic disk image comparing the size of the disk image file with the space used by file systems inside the image. For a optimal resource allocation, they should not be very different.
Currently supported file systems are:
- New Technology File System (NTFS), for Windows computers
- Hierarchical or Apple File System (HFS+ or APFS), for macOS
- Extended File System (EXT), used in most linux desktops
Also reads BTRFS or XFS (Linux), but in these cases compression does not work.
The compact operation pulls blocks of data from the end of the disk image to space that was detected to be not in use by file systems.
To begin a scan is made to detect blocks of data that are not in use by file systems, and the disk image structure is updated marking those blocks as if they were never used. Then blocks with effective data are moved from the end of the disk image to the space that was recovered by the previous operation.
Finally the image structure is updated to reflect the new position of the moved blocks, and the image file size is trimmed. Updates to the image structure are temporarily saved on the host media and will be written to the image at next program execution, in case of a recoverable hardware failure.
The copy operation begins with a scan to detect blocks of data that are not in use by file systems. The new image is created ignoring those blocks, and blocks that would otherwise be completely filled with zeros.
The format of the new disk image can be select in the Copy Disk Image dialog with one these file extensions:
- VDI, Virtual Disk Image for Oracle VirtualBox
- VMDK, Virtual Machine Disk for VMware products
- VHD, Virtual Hard Disk for Microsoft products
- RAW, for a complete disk image
Copyright © 2016-2024 Rui Baptista
Licensed under the Apache License, Version 2.0. You may obtain a copy of the License released under the Apache License 2.0. Software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
This product includes Apache Commons CLI software Copyright 2002-2024 The Apache Software Foundation.
The application icon is a derivative work of original made by Susumu Yoshida (Copyright © 2009 McDo DESIGN.com).
The other icons that identify image disks in the view panel are copyright-protected computer icons of file formats. The author believes that the exhibition of icons to identify the file formats in question qualifies as fair use.