LBAcache/COMcache, in the version of Jan 24 2002, all written and conceived by Eric Auer . Welcome to Erics GPLed* LBAcache hard disk cache! You need some XMS, at least a 386 CPU and some (...) drive to cache to use this. See the footnote on the GPL. It is GPL version 2, by the way. In short: This is FREE software, intended to be useful, but WITHOUT ANY GUARANTEE. And it comes with the (nasm) source code. Only read access is cached, so no waiting for that "It is now safe to turn off your PC" message - but also somehow suboptimal performance. I recommend setting BUFFERS to 4*(cluster size in KByte) + 2 in (fd)config.sys to maybe have some small write cache as well. By the way, smartdrv usually offers 32 write buffers. Next, the usual WARNING: This is a beta version of a thing that interacts with your hardware very closely. So be warned that any bug I have not found yet may destroy your data! Do BACKUPS of your data before you start using this and once a while, stop using this cache to make fresh versions of those backups, etc.! You may have guessed it, but I would not have released this if it were destroying data all the time. So here are the good news: The cache has been NICE to my data recently, so I hope it will be to yours as well. Only drives supported by the BIOS are supported, but no special ones like CD drives and ZIP drives and similar. *** How to use the cache: *** You can load the cache in fdconfig.sys or config.sys using DEVICE=LBACACHE.SYS [arguments] or DEVICEHIGH=LBACACHE.SYS [arguments] or you can load it from the DOS prompt or in autoexec.bat using LBACACHE.COM [arguments] or LOADHIGH LBACACHE.COM [arguments] which should all work roughly the same, but maybe some systems will not work with ...HIGH... and others will only work with ...HIGH... (please tell me if this is the case for you). There are three "UNCACHE" options: INFO shows statistics on loaded instances of LBACACHE. The STOP option removes all instances of LBACACHE. Finally, the SYNC option empties/flushes/ syncs all cache instances for drives A: .. F: by "ejecting" the associated media. STOP also frees the XMS used. The argument syntax of the cache itself is currently as follows: [BUF] digit[text] will set the buffer size to digit*512k. 0 will set to 256k, and the maximum value is 8 (for 4M) for no real reason now. DRV list will only cache drives in list, using the BIOS numbers. C = 0 = BIOS 0x80 = /dev/hda, D = 1 = BIOS 0x81 = /dev/hdb ... up to F. FLOP will enable caching for floppies, but only if they allow change detection. WARNING: see the note on havoc with this below! STAK Activates an internal stack (for use with FreeDOS, which has only 192 bytes of kernel stack or so) - 500 bytes more RAM used. {HELP|?} Shows a help message. WARNING: If your floppy change detection does not work and/or the floppy cache function (new, Jan 2002) is buggy, you have to flush the cache by hand using "uncache f" or data from several floppies may be mixed in an awful way in the lbacache and/or DOS buffers, and this mix may even end up being written back, destroying data on your floppy disk. Also, any geometry above 1.44 MBy is rejected at startup, BUT if you later change it, lbacache will not detect the fact and will horribly fail for that floppy. Using other geometries than 1.44 MBy for floppies will probably cause data inconsistencies, so do NOT do it unless you are a programmer trying to fix this bug! After all, the floppy cache is a quite new feature and less tested than the hard disk cache. Examples: lbacache buf 7 device=lbacache.sys drv d buf 5 flop lbacache info The defaults are to cache CDEF and set the buffer size to 2M. *** Technical stuff (do not read this if you do not want to!): *** If no LBA BIOS is found, reads will be converted from CHS to LBA and back again on demand, and you will even be able to do LBA reads after loading the cache. No such feature is planned for the writes for now. Mail me if you have use for them. Floppy access will always be converted to CHS style. Reads will be split up: A sector found in the cache will be read directly, while disk reads are collected and done in larger chunks if possible (new 1/2002). This will hopefully speed up reading larger files with FreeDOS kernels 1.1.25 and better a lot (compared to the situation with older kernels or older versions of LBAcache which made no use of the new kernel feature). The behaviour of the cache is to a very big extend controlled by selecting one of the binsel.* as source of the binsel.asm, but only binsel.asm (binsel.ni2) is maintained now. Maybe you have to adjust the others to work with the current version. The current version of binsel.asm uses a table with 8 bytes of DOS memory per main entry, which can hold up to 16 sub entries. The current setting is 4 sub entries per main entry - thus you need 4k of DOS memory for 1M of XMS memory (2k sectors). The old version binsel.nil has no subentries and uses a lot of memory. The even older binsel.cnt does the same, but tries to be clever in deciding which part of XMS to reuse first as it runs out of memory, which can on the other hand take a lot of CPU time! My plan is to add a bit of cleverness to binsel.asm without taking too much time. Comments on the sub entries per main entry ratio and the hashing and the cleverness are welcome. Questions on the API used by binsel are also welcome, if you want to do your own "binsel plugin". * free as beer and speech and has to stay like that. Feel free to improve this, but please tell me about your new versions... And do not forget to mention me in the credits, or you will get bad karma!