In order, to implement dynamic multilevel indexing, B-tree and B+ tree are generally employed. The drawback of B-tree used for indexing, however is that it stores the data pointer (a pointer to the disk file block containing the key value), corresponding to a particular key value, along with that key value in the node of a B-tree. This technique, greatly reduces the number of entries that can be packed into a node of a B-tree, thereby contributing to the increase in the number of levels in the B-tree, hence increasing the search time of a record.
TreeSize is another popular option. It has a clickable Treemap that’s off by default; instead, you start with a folder tree with a built-in bar graph, like the top pane in WinDirStat. Tree -du -shaC -L 2.indents and colorizes nicely however the reported sizes are a lie. To get the real sizes one must: tree -du -shaC.which is to say that you only get the true sizes if you let 'tree' show you the entire directory structure. Unlike tree shears, the CVR Disk Tree Cutter requires no external power source or stopping and waiting for hydraulic jaws to open and close around the tree. The CVR Disk Tree Cutter can cut hundreds of trees per hour. How the CVR Disk Tree Cutter works: Just like a pipe cutter slices through metal, circular blades rotate as the CVR Disk Tree. Disk found in: All Star Sports Orange Sports Discs, 2-ct. Packs, White Foam Disks, 2-ct. Packs, Russel Stover Peppermint Flavored Disk Candies, 2.5 oz. Bags, Coastal Bay Confections Butterscotch Disks, 10 oz. Diamond Mowers’ Skid-Steer Forestry Disc Mulcher is the best solution for mulching smaller-diameter trees and brush. The design of the disc acts like a flywheel to store energy. This stored energy combines with hydraulic power to enable you to mulch any trees or brush in your path.
Disk Tree View
B+ tree eliminates the above drawback by storing data pointers only at the leaf nodes of the tree. Thus, the structure of leaf nodes of a B+ tree is quite different from the structure of internal nodes of the B tree. It may be noted here that, since data pointers are present only at the leaf nodes, the leaf nodes must necessarily store all the key values along with their corresponding data pointers to the disk file block, in order to access them. Moreover, the leaf nodes are linked to provide ordered access to the records. The leaf nodes, therefore form the first level of index, with the internal nodes forming the other levels of a multilevel index. Some of the key values of the leaf nodes also appear in the internal nodes, to simply act as a medium to control the searching of a record.
![Disk Disk](https://thumbs.dreamstime.com/z/sekhmet-ptah-18006153.jpg)
Praise v1 0 3 – facebook and twitter share. From the above discussion it is apparent that a B+ tree, unlike a B-tree has two orders, ‘a’ and ‘b’, one for the internal nodes and the other for the external (or leaf) nodes.
The structure of the internal nodes of a B+ tree of order ‘a’ is as follows:
- Each internal node is of the form :
<P1, K1, P2, K2, …., Pc-1, Kc-1, Pc>
where c <= a and each Pi is a tree pointer (i.e points to another node of the tree) and, each Ki is a key value (see diagram-I for reference). - Every internal node has : K1 < K2 < …. < Kc-1
- For each search field values ‘X’ in the sub-tree pointed at by Pi, the following condition holds :
Ki-1 < X <= Ki, for 1 < i < c and,
Ki-1 < X, for i = c
(See diagram I for reference) - Each internal nodes has at most ‘a’ tree pointers.
- The root node has, at least two tree pointers, while the other internal nodes have at least ceil(a/2) tree pointers each.
- If any internal node has ‘c’ pointers, c <= a, then it has 'c – 1' key values.
Diagram-I
The structure of the leaf nodes of a B+ tree of order ‘b’ is as follows:
Disk Tree File Size
- Each leaf node is of the form :
<<K1, D1>, <K2, D2>, …., <Kc-1, Dc-1>, Pnext>
where c <= b and each Di is a data pointer (i.e points to actual record in the disk whose key value is Ki or to a disk file block containing that record) and, each Ki is a key value and, Pnext points to next leaf node in the B+ tree (see diagram II for reference). - Every leaf node has : K1 < K2 < …. < Kc-1, c <= b
- Each leaf node has at least ceil(b/2) values.
- All leaf nodes are at same level.
Diagram-II
Using the Pnext pointer it is viable to traverse all the leaf nodes, just like a linked list, thereby achieving ordered access to the records stored in the disk.
A Diagram of B+ Tree –
Advantage –
A B+ tree with ‘l’ levels can store more entries in its internal nodes compared to a B-tree having the same ‘l’ levels. This accentuates the significant improvement made to the search time for any given key. Having lesser levels and presence of Pnext pointers imply that B+ tree are very quick and efficient in accessing records from disks.
A B+ tree with ‘l’ levels can store more entries in its internal nodes compared to a B-tree having the same ‘l’ levels. This accentuates the significant improvement made to the search time for any given key. Having lesser levels and presence of Pnext pointers imply that B+ tree are very quick and efficient in accessing records from disks.
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directory size and usage analyzer
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Version 4.4.2 for Windows, Multilingual
7MB download / 8MB installed
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7MB download / 8MB installed
Notes | Antivirus Scan | Details
TreeSize Free Portable can run from a cloud folder, external drive, or local folder without installing into Windows. It's even better with the PortableApps.com Platform for easy installs and automatic updates.
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Description
Every hard disk is too small if you just wait long enough. TreeSize Free tells you where precious disk space has gone. TreeSize Free shows you the size of and drive or folder, including its subfolders. Expand folders in an Explorer-like fashion and see the size of every subfolder. All results can also be drilled down to the file level. Scanning operations run in a thread, so you can already see results while TreeSize Free is working. The disk space tool now also includes the main feature of our discontinued freeware NTFSRatio: TreeSize Free can display the NTFS compression rate and apply the NTFS compression on directory branches.
App Notes
Network Drives: TreeSize Free will not work on network drives. Purchasing TreeSize Personal or Professional will enable this functionality.
Changing Languages: The app is in English by default. To switch to German, rename TreeSizeFree.DE.disabled to TreeSizeFree.DE within the TreeSizeFreePortableAppTreeSizeFree directory.
Support
For help with this app, please see the following:
- PortableApps.com Forum: Portable App Support
Download Details
- Publisher: JAM Software & PortableApps.com (Doug Akins)
- Date Updated: 2020-06-07
- Date Added: 2012-10-20
- System Requirements: Windows Vista, 7, 8, 10
- App License: Freeware
- Source: PortableApps.com Launcher, PortableApps.com Installer
- MD5 Hash: dad8353ae5e590052e2b7921d9a9032f
- SHA256 Hash: 9cf50fdfc41be02c975d63a043e53b8be902bfcba273921f448c0c2224521c9f
TreeSize Free is packaged for portable use with permission from the publisher.