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FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mNAME 0mFastDisk - Disk-Optimizer/Copier 1mSYNOPSIS FastDisk 0m[ [FROM] <device> ] [ [TO] <device> ] [ FORMAT | NOFORMAT ] [ VERIFY | NOVERIFY ] [ [FILESYSTEM] FFS | SFS | SRC | DEV ] [ [BUFFERMODE] HUMBLE | FAIR | GREEDY | IGNORANT ] [ [DISPLAY] CLI | WINDOW ] 1mDEFAULTS FastDisk 0mDF0: TO DF1: FORMAT NOVERIFY DEV GREEDY WINDOW 1mOVERVIEW FastDisk 0mis a high-performance disk optimizing tool which decreases access time for files and directories. This is achieved by creating a disk with an optimized sector layout, including linear directory layout, .info and small file precedence and minimized track-boundary crossing for data blocks. 1mFastDisk 0mwill work with any 4mAmigaDOS0m device of any size provided that the underlying Exec-device supports trackdisk.device commands (i.e. all block-oriented Exec-devices). 1mFastDisk 0msupports blocksizes other than 512 Byte. 1mFastDisk 0msupports the standard 4mAmigaDOS0m filesystem, the fast filing system and automatic or forced filesystem conversion. 1mFastDisk 0mperforms intelligent block pre-caching, reducing execution time to that of a standard 4mDiskCopy0m or less. 1mFastDisk 0mhas four different modes of operation, ranging from a minimum memory mode without block caching to reckless memory eating for maximum performance. 1mFastDisk 0mis able to detect low-memory situations (via 3mASDG-LowMem.library 0m) and will release allocated non-vital memory if these occur. 1mFastDisk 0mhas a nice intuition-interface, but can also be used in a CLI-only mode and can take its parameters from the commandline, WorkBench-Tooltypes, Manx environment and Commodore ENV: environment. 1mFastDisk 0mruns under KickStart 1.2 / 1.3 and 2.0 and needs the 3marp.library(V.39+) 0mto run. The 3mASDG-LowMem.library 0mis recommended for full functionality but not mandatory. Torsten Stolpmann -1- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mDESCRIPTION FastDisk 0mcan be started from either 4mWorkBench0m or 4mCLI0m. The following 4mCLI0m parameters are possible: 1mFROM 0m<1mdevice0m> Using the 1mFROM 0mparameter you may specify the source device which contains the 4mAmigaDOS0m volume you want to optimize. The ':' character must be included for the device name to be recognized. The 1mFROM 0mkeyword is optional and may be omitted. Default source device is 4mDF00m:. 1mTO 0m<1mdevice0m> Using the 1mTO 0mparameter you may specify the destination device which contains the disk to be overwritten with the contents of the source disk. The 1mTO 0mkeyword is optional and can be omitted unless you want to specify the destination device before the source device, in which case it is mandatory. The ':' character must be included for the device name to be recognized. Default destination device is 4mDF10m:. Please note that source and destination may not be equal, 'on-disk' optimization will be covered in the next release. 1mFORMAT 0mThis parameter tells 1mFastDisk 0mto format the whole destination disk. This is needed for unformatted disks and generally useful for every optimization because it wipes out all former contents of the destination disk, which may irritate disk-repair utilities such as 4mDiskDoctor0m or 4mFixDisk0m (especially 4mDiskDoctor0m, it gets confused often). This is the default option. 1mNOFORMAT FastDisk 0mwill only write those tracks which contain data, speeding up the optimization (with the above disadvantages). If 1mFastDisk 0mdetects an unreadable disk in the destination device this option is automatically switched to 1mFORMAT0m. 1mVERIFY 0mThe complete destination disk will be scanned for read-errors after the optimization. 1mNOVERIFY 0mNo verification of the destination disk. This is the default option. Torsten Stolpmann -2- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mFILESYSTEM SFS 0mThe destination disk will be a standard file-system disk. The 1mFILESYSTEM 0mkeyword is optional. 1mFILESYSTEM FFS 0mThe destination disk will be a fast file-system disk. The 1mFILESYSTEM 0mkeyword is optional. 1mFILESYSTEM SRC 0mThe destination disk will have the same file-system type as the source disk. The 1mFILESYSTEM 0mkeyword is optional. 1mFILESYSTEM DEV 0mThe destination disk will have the file-system type which is supplied by the 4mMountList0m entry 4mDosType0m for the destination device. If this entry is not present (KickStart 1.3 and earlier) default is the standard file-system. The 1mFILESYSTEM 0mkeyword is optional. This is the default option. 1mBUFFERMODE HUMBLE 0mIn 1mHUMBLE 0mmode 1mFastDisk 0mwill allocate as little memory as possible to do the optimization. This of course leads to a cutdown in execution speed, due to the lack of block-caching. The advantage of this option is the constant memory usage after initialization. In all other modes, memory will be dynamically allocated when needed. The 1mBUFFERMODE 0mkeyword is optional. 1mBUFFERMODE FAIR 0mWith this mode selected, all memory currently not used will be returned to the system immediatly and block-caching will be turned on. When receiving a notification of a Low-Memory situation (via 4mASDG0m-4mLowMem0m.4mlibrary0m if installed) memory used for pre-cached blocks will be given back and 1mFastDisk 0mwill continue its operation in 1mHUMBLE 0mmode. The 1mBUFFERMODE 0mkeyword is optional. 1mBUFFERMODE GREEDY 0mUnused memory is cached to avoid subsequent 4mAllocMem0m() - 4mFreeMem0m() calls. 1mFastDisk 0mwill honor Low-Memory situations by freeing non-vital memory, but will continue in 1mGREEDY 0mmode. The 1mBUFFERMODE 0mkeyword is optional. This is the default option. Torsten Stolpmann -3- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mBUFFERMODE IGNORANT FastDisk 0mwill ignore all Low-Memory situations and will keep all memory until completion. 1mFastDisk 0mwill also raise its Task-Priority to 1. The 1mBUFFERMODE 0mkeyword is optional. 1mDISPLAY CLI 0mWith this option 1mFastDisk 0mwill not open its Intuition-Window and will use the CLI-Window it has been started from for output. All neccessary parameters differing from the default/environment settings must be provided in the command line. 1mFastDisk 0mwill ask you to insert the source/destination disks in the appropriate devices and to press <RETURN>. When started non-interactive (for example with 3mRun FastDisk) 0m1mFastDisk 0mwill start immediatly, making it possible to use it in a script or the startup-sequence. The 1mDISPLAY 0mkeyword is optional. 1mDISPLAY WINDOW 0mWith this option 1mFastDisk 0mwill open its Intuition-Window where all of the above options can be selected via Gadgets. The 1mDISPLAY 0mkeyword is optional. This is the default option. All the above parameters can be specified in the environment variable 4mFASTDISKOPTS0m also (for example: 3mSet FASTDISKOPTS="VERIFY BUFFERMODE FAIR") 0mto override the default settings. The WorkBench-Tooltype settings are of the form 3mKEYWORD=OPTION 0mwhere 3mKEYWORD 0mis one of 1mFROM0m, 1mTO0m, 1mFILESYSTEM0m, 1mBUFFERMODE0m, 1mFORMAT 0mand 1mVERIFY 0mand 3mOPTION 0mone of the options listed above (the valid options for 1mFORMAT 0mand 1mVERIFY 0mare 1mON 0mor 1mOFF 0m). When started from Workbench, 1mFastDisk 0mwill always open its Intuition-Window. CLI-Parameters and ToolTypes will override the default and environment settings. You can use 1mFastDisk 0mwith any combination of devices. The only condition that must be fulfilled is that the data on the source device must fit onto the destination device. Torsten Stolpmann -4- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mTECHNICAL NOTES 0mMEMORY REQUIREMENTS Every effort was taken to make memory-usage as low as possible while retaining maximum performance. Each file/directory/link on the source disk is represented internally by a 32-Byte structure which contains all the necessary information. This and a dynamic map of pre-cached sectors (only for non-humble modes) are the main memory-sinks. By comparison, additional memory allocation is neglegible. 1mFastDisk 0mdoes not rely on large contigous memory-areas like many other optimizers. Using 1mHUMBLE 0mmode, it is possible to optimize a 30 MB Harddisk-Partition with 512 KB Amigas. 1 MB Memory should be sufficient for 130 MB Partitions. These are rough estimates, as memory usage mainly depends on the number of files, not on the size of the partition. OPTIMIZATION METHODS In this release I have tried to achieve the following three optimization-goals. Goal 1: Fast directory listings This is done by placing all file-headers in the same physical order on the disk as read by the filing system, including the ascending sorting of hash-chains which is required for the correct behaviour of the ExNext() function in KickStart 2.0. In addition these blocks are centered around the RootBlock. Directory blocks are placed immediatly after the root and bitmap blocks for fast access to deeper nested levels. Goal 2: Fast read-access for 3mspecial 0mFiles To obtain minimum access time for small or often accessed files, the data blocks of these files are placed immediatly after the corresponding header blocks. These 3mspecial 0mfiles include all files which contain only one or two data blocks or whose names are 'System-Configuration', 'Startup-Sequence', 'MountList' or 'Shell-Startup' or end in '.info'. This has a negative influence on Goal 1, especially with directories containing many special files (by increasing the number of tracks to be read), but is more efficient (regarding the advantages). Goal 3: Minimimum track boundary crossing The remaining sectors on the destination disk are filled with the data-sectors of the non-special files. This is done in such a way, that each file will cross as few track boundaries as possible, so that the number of track-seeks and (for track-oriented devices such as trackdisk.device) the number of complete tracks to be read is minimized. Torsten Stolpmann -5- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mBUGS0m/1mLIMITATIONS 0m- 4mSoftlinks0m are not supported, since Kickstart 2.0 does currently not support them (V37.166). 1mFastDisk 0mis able to detect and suppress Softlinks (they will not be present on the destination disk). - The 4mMountList0m entries 4mBootBlocks0m, and 4mInterleave0m are ignored in this release. - 1mFastDisk 0mshould detach itself if the 1mWINDOW 0moption is provided. 1mLEGAL STUFF 0m/ 1mDISTRIBUTION FastDisk 0mVersion 1.9 is Copyright 1991 by Torsten Stolpmann, all rights reserved. The author takes absolutely no responsibility for the functionality or the possible damage done by this software. Use this at your own risk. 1mFastDisk 0mVersion 1.9 is freely distributable for non-commercial purposes. The author hereby grants Fred Fish the right to include this software in his library of freely distributable software. Lots of time and sweat were spent to make this an efficient, reliable and hopefully useful tool. If you like 1mFastDisk 0mand you can spare some money, I won't object if you send some. Send flames, suggestions, bug reports and lots of money to the following adress: Torsten Stolpmann Wilhelm-Raabe-Str. 26 / App. 911 W 6750 Kaiserslautern Germany Phone: 0631/22781 You may also send email to: stolp@informatik.uni-kl.de The adress above is valid upto November 1991. The new adress will then be: Industriestr. 7 W 6750 Kaiserslautern (No new phone-number yet) Torsten Stolpmann -6- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mACKNOWLEDGEMENTS 0mThis document was created with 1mnroff 10m.1m5 0m- ported by Olaf Seibert (KosmoSoft). Window, Requesters and Gadgets were created with 1mGadgetEd 20m.1m3 0mby Jan van den Baard (Jaba Developments). 1mFixDisk 10m.1m2 0mby Werner Günther was an often used tool for Disk-Validation during development. Jörg Mayer hacked up the fmsdisk.device to emulate disks of any size. This way it was possible to test 1mFastDisk 0mon 330 MB Partions with a 30 MB Harddisk. Additional thanks for suggestions, beta testing, manual proofreading and bug reports to: Jörg Mayer, Bernd Reh, Deon Ramsey, Volker Rudolph and Oliver Wagner and all the others who have sent letters or email ... Torsten Stolpmann -7- Version 1.9 FastDisk(1) AMIGA Programmer's Manual FastDisk(1) 1mHISTORY 0mVersion 1.5: First public release (1987). Version 1.8: Second public release (1989) (minor rewrite). Known Bugs removed: 1.5 can't process files with length 0. Performance loss if out of memory. New Features: Fast memory support (1.5 used only chipmem). Supports all kinds of devices (1.5 only supported trackdisk.device). Manx-Style environment support. Version 1.9: Third public release (July 1991) (complete rewrite). Known Bugs removed: No bugs reported. New Features: Fast-FileSystem support. Intuition interface. Low-Mem library support. New asynchronous I/O routines. Algorithm for minimized track boundary crossing of file data-blocks. New memory managment. Removed necessity to hold Header-Blocks in memory. Support for different blocksizes. Verify mode added. Lots more... There exists also a program called 3mFastDisk II 0mwritten by Oliver Wagner (published on Fish Disk). This is mainly an 'enhancement' of Version 1.5 with an Intuition-Interface. This program is completely useless due to a serious bug created by the global optimizer. Don't blame me for that version, it was released before I could test or authorize it. Due to this incident there will be no more source-code releases of 1mFastDisk0m. See ya in version 2.0 ... Torsten Stolpmann -8- Version 1.9