> If "rtroy" supposition was held up disk performance would suffer > dramatically. This is the very old and very tired dogmatic argument which has been disproven repeatedly throughout computing history. ...It could also be that you have not understood - perhaps I have not articulated - the argument correctly. > All OS-es use write caches, including Windows, though you > have the option to turn it off. Not using caches leads to poor disk > performance, especially on multi-user systems, disks with small buffers, > and where you are regularly rewriting the same area. This is not a discussion about to use or not use disk caches. Of course disk caches are wonderful things. The point is to not allow a condition to occurr in which the STRUCTURE OF THE DISK CHANGES _without_ that change having been written completely to disk prior to permitting user access occurr. A properly managed cache knows the difference between things it can write on convenience and things that should be written "now." > Also note that applications also use write caches, so even if your OS > didn't cache and you powered off the system you would probably lose data > with the application cache. If you really want data written immediately > don't use "stdio" and do set O_SYNC when you "open()" the file. I've > done so when I've had to and the performance difference is enormous. This paragraph clearly shows that you have not paid attention to my statements. Either that, or you're unfamillar with the difference between disk structural changes and the data contained therein. A previous poster had it right when he wrote something like "disk stucture = meta-data". BINGO! We are _not_ talking about user-data - at least, I'm not. > If Unix is stupid because of this, all modern computers are stupid. This > is standard computing practice, Bill Gates included. Well... It's true that Unix, up until relatively recently, has had this rather stupid flaw. They band-aided the thing with fsck - an embarassment in my view - because it was _required_ with their strategy. It sucks. The argument was that, "these are research systems." And, indeed, most were. How do I know this? I was there. It's a very sad truth that computer science has suffered greatly because of a mis-guided perception that anything older than about 5 years is ancient history and not worth learning. There have been no less than three complete generational changes - epochs through which similar or identical lessons had to be re-learned because of this short-sightedness. Note, we still use the wheel even though it's more than 2000 years old, though we have improved upon it. Too bad we haven't done so well in the short history of computing. -shrug- Anyway, as for Windows, it always did suck. I remember when it first hit the streets. I took a serious look because at the time I was writing my own operating system to control ships, refineries and pipelines. It was immediately obvious to me that it was antiquated before it even started. One of the most obvious flaws was that it didn't have a proper inturrupt system - and that remained true until about Windows 95 - which came out in '97 if I recall correctly. It was only when Dave Cutler, inventor of RSX-11, and subsequently the primary architect of VAX/VMS, went over to the dark side when Ken Olson snubbed him, demanding he close DecWest (in Seattle)... Ken made the big mistake of letting him and his code go. ...That code line became Windows NT... As for "all modern computing" - well, all modern computing does not include some really wonderful technologies which were created. These have been largely lost due to two primary factors: The failure of many big computing companies to correctly handle the microcomputer market, and Gate's illegally won monopoly. Sure, there are other reasons, but it's a huge mistake to equate modern computing with the most intelligent computing. I'm guessing that all of this is unfamillar to you. I lament that. That old quote is true, I think, the one that says that those who for get the past - or who never learned it - are condemned to repeat it... Regards, Richard
