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Disk Care 2.0



In terms of reported memory usage, CARE has the highest memory consumption. However, in general the measured memory is not strictly required. At its core, CARE needs the reads and the hash tables to be located directly in memory. The remaining free memory, if any, is then utilized to store temporary results. On systems with less memory this leads to results being stored on disk instead at a cost of performance. A similar principle applies to GPU memory. GPU versions of CARE occupy close to the maximum of available GPU memory, which is 24 GB. They attempt to cache as much read data as possible on the GPU for fast access. The remaining read data has to be fetched from system memory.


Background context: The paper ''Nomenclature and classification of lumbar disc pathology, recommendations of the combined task forces of the North American Spine Society, the American Society of Spine Radiology and the American Society of Neuroradiology,'' was published in 2001 in Spine ( Lippincott, Williams & Wilkins). It was authored by David Fardon, MD, and Pierre Milette, MD, and formally endorsed by the American Society of Spine Radiology (ASSR), American Society of Neuroradiology (ASNR), and North American Spine Society (NASS). Its purpose was to promote greater clarity and consistency of usage of spinal terminology, and it has served this purpose well for over a decade. Since 2001, there has been sufficient evolution in our understanding of the lumbar disc to suggest the need for revision and updating of the original document. The revised document is presented here, and it represents the consensus recommendations of contemporary combined task forces of the ASSR, ASNR, and NASS. This article reflects changes consistent with current concepts in radiologic and clinical care.




Disk Care 2.0



The Healthy Indiana Plan is a health-insurance program for qualified adults. The plan is offered by the State of Indiana. It pays for medical costs for members and could even provide vision and dental coverage. It also rewards members for taking better care of their health. The plan covers Hoosiers ages 19 to 64 who meet specific income levels. See below if your 2022 income qualifies.


Registry Defrager rebuilds PC's Registry, making the entire system run quicker and smoother. The Game Booster concentrates every system resource for gaming purpose. File Shredder helps you to shred and permanently remove unwanted files/folders from your computer beyond recovery. Disk Wipper completely erases the free space in your hard disk to prevent other one to recovery the removed files in the disk.


File Recovery tool helps you to find the files you have deleted before and you can recovery any of them easily. Registry Backup and Restore helps you to backup or restore your Registry with a simple click. Password Manager is designed to help you create secure passwords that are extremely difficult to crack or guess. Also it can help you to manage your password, account and other private information. Disk Doctor helps you to check your hard disk both in I/O access and file system and give you a full report for the checking.


One feature of Windows NT/2000's (Win2K) C2-compliance is that itimplements object reuse protection. This means that when an applicationallocates file space or virtual memory it is unable to view data thatwas previously stored in the resources Windows NT/2K allocates for it.Windows NT zero-fills memory and zeroes the sectors on disk where a fileis placed before it presents either type of resource to an application.However, object reuse does not dictate that the space that a fileoccupies before it is deleted be zeroed. This is because Windows NT/2Kis designed with the assumption that the operating system controlsaccess to system resources. However, when the operating system is notactive it is possible to use raw disk editors and recovery tools to viewand recover data that the operating system has deallocated. Even whenyou encrypt files with Win2K's Encrypting File System (EFS), a file'soriginal unencrypted file data is left on the disk after a new encryptedversion of the file is created.


The only way to ensure that deleted files, as well as files that youencrypt with EFS, are safe from recovery is to use a secure deleteapplication. Secure delete applications overwrite a deleted file'son-disk data using techniques that are shown to make disk dataunrecoverable, even using recovery technology that can read patterns inmagnetic media that reveal weakly deleted files. SDelete (SecureDelete) is such an application. You can use SDelete both to securelydelete existing files, as well as to securely erase any file data thatexists in the unallocated portions of a disk (including files that youhave already deleted or encrypted). SDelete implements the Departmentof Defense clearing and sanitizing standard DOD 5220.22-M, to give youconfidence that once deleted with SDelete, your file data is goneforever. Note that SDelete securely deletes file data, but not filenames located in free disk space.


SDelete is a command line utility that takes a number of options. Inany given use, it allows you to delete one or more files and/ordirectories, or to cleanse the free space on a logical disk. SDeleteaccepts wild card characters as part of the directory or file specifier.


Securely deleting a file that has no special attributes is relativelystraight-forward: the secure delete program simply overwrites the filewith the secure delete pattern. What is more tricky is securely deletingWindows NT/2K compressed, encrypted and sparse files, and securelycleansing disk free spaces.


Compressed, encrypted and sparse are managed by NTFS in 16-clusterblocks. If a program writes to an existing portion of such a file NTFSallocates new space on the disk to store the new data and after the newdata has been written, deallocates the clusters previously occupied bythe file. NTFS takes this conservative approach for reasons related todata integrity, and in the case of compressed and sparse files, in casea new allocation is larger than what exists (the new compressed data isbigger than the old compressed data). Thus, overwriting such a file willnot succeed in deleting the file's contents from the disk.


To handle these types of files SDelete relies on the defragmentationAPI. Using the defragmentation API, SDelete can determine preciselywhich clusters on a disk are occupied by data belonging to compressed,sparse and encrypted files. Once SDelete knows which clusters containthe file's data, it can open the disk for raw access and overwrite thoseclusters.


Cleaning free space presents another challenge. Since FAT and NTFSprovide no means for an application to directly address free space,SDelete has one of two options. The first is that it can, like it doesfor compressed, sparse and encrypted files, open the disk for raw accessand overwrite the free space. This approach suffers from a big problem:even if SDelete were coded to be fully capable of calculating the freespace portions of NTFS and FAT drives (something that's not trivial), itwould run the risk of collision with active file operations taking placeon the system. For example, say SDelete determines that a cluster isfree, and just at that moment the file system driver (FAT, NTFS) decidesto allocate the cluster for a file that another application ismodifying. The file system driver writes the new data to the cluster,and then SDelete comes along and overwrites the freshly written data:the file's new data is gone. The problem is even worse if the cluster isallocated for file system metadata since SDelete will corrupt the filesystem's on-disk structures.


The second approach, and the one SDelete takes, is to indirectlyoverwrite free space. First, SDelete allocates the largest file itcan. SDelete does this using non-cached file I/O so that the contentsof the NT file system cache will not be thrown out and replaced withuseless data associated with SDelete's space-hogging file. Becausenon-cached file I/O must be sector (512-byte) aligned, there might besome leftover space that isn't allocated for the SDelete file evenwhen SDelete cannot further grow the file. To grab any remaining spaceSDelete next allocates the largest cached file it can. For both ofthese files SDelete performs a secure overwrite, ensuring that all thedisk space that was previously free becomes securely cleansed.


On NTFS drives SDelete's job isn't necessarily through after itallocates and overwrites the two files. SDelete must also fill anyexisting free portions of the NTFS MFT (Master File Table) with filesthat fit within an MFT record. An MFT record is typically 1KB in size,and every file or directory on a disk requires at least one MFT record.Small files are stored entirely within their MFT record, while filesthat don't fit within a record are allocated clusters outside the MFT.All SDelete has to do to take care of the free MFT space is allocatethe largest file it can - when the file occupies all the available spacein an MFT Record NTFS will prevent the file from getting larger, sincethere are no free clusters left on the disk (they are being held by thetwo files SDelete previously allocated). SDelete then repeats theprocess. When SDelete can no longer even create a new file, it knowsthat all the previously free records in the MFT have been completelyfilled with securely overwritten files.


The reason that SDelete does not securely delete file names whencleaning disk free space is that deleting them would require directmanipulation of directory structures. Directory structures can have freespace containing deleted file names, but the free directory space is notavailable for allocation to other files. Hence, SDelete has no way ofallocating this free space so that it can securely overwrite it.


MiniTool Partition Wizard Free Edition is a free partition manager & disk benchmarking tool. Its disk benchmark feature can help you measure storage performance by testing its sequential and random read/write speeds. 2ff7e9595c


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