pawn@wpi.wpi.edu (Kevin Goroway) (02/16/89)
Is there any reason to add a MaxTransfer to a mountlist if the drive works fine without it? Is there a possibility of a speed INCREASE with it? thanks... Pawn@wpi.bitnet Pawn@wpi.wpi.edu
w-colinp@microsoft.UUCP (Colin Plumb) (02/17/89)
pawn@wpi.wpi.edu (Kevin Goroway) wrote: > Is there any reason to add a MaxTransfer to a mountlist if the drive works > fine without it? Is there a possibility of a speed INCREASE with it? NO. Well, maybe with *really* screwed-up driver software, but all MaxTransfer does is compensate for a common bug in device driver software, an upper limit on data-transfer request size. The old FS would only read and write a block at a time, so as long as your driver could hanle that, everything would work. The FFS tries to send large single requests, and some .device drivers broke. Thus, the kludge in the FFS. If your .device driver can handle them, large requests are invariably faster than multiple small ones, and you should let the FFS use them. >> MaxTransfer is a kludge and will go away when << >>.device driver writers get their acts together.<< Oops... that's maybe a bit more forceful than necessary. But you get the idea. -- -Colin (uunet!microsoft!w-colinp) "Don't listen to me. I never do."
lphillips@lpami.wimsey.bc.ca (Larry Phillips) (02/19/89)
In <867@wpi.wpi.edu>, pawn@wpi.wpi.edu (Kevin Goroway) writes: >Is there any reason to add a MaxTransfer to a mountlist if the drive works >fine without it? Is there a possibility of a speed INCREASE with it? >thanks... MaxTransfer is a limiting factor, and should not be used at all if your driver/controller is capable of handling any length request. IF the manufacturer specifies a MaxTransfer value, you should use it, or you will have GURUs and file corruption problems. -larry -- Frisbeetarianism: The belief that when you die, your soul goes up on the roof and gets stuck. +----------------------------------------------------------------------+ | // Larry Phillips | | \X/ lphillips@lpami.wimsey.bc.ca or uunet!van-bc!lpami!lphillips | | COMPUSERVE: 76703,4322 | +----------------------------------------------------------------------+
ba@m-net.UUCP (Bill Allen) (03/01/89)
In <867@wpi.wpi.edu>, pawn@wpi.wpi.edu (Kevin Goroway) writes: >Is there any reason to add a MaxTransfer to a mountlist if the drive works >fine without it? Is there a possibility of a speed INCREASE with it? >thanks... I've been playing with MaxTransfer and Buffers, increasing and decreasing the values. I've noticed very little, if any HD improvement. I do notice that even setting both values at a minimum, I use 40K per partition per drive. Is this normal? Two drives, each divided into four partitions uses an incredible amount of RAM just by mounting them.
lphillips@lpami.wimsey.bc.ca (Larry Phillips) (03/03/89)
In <2940@m2-net.UUCP>, ba@m-net.UUCP (Bill Allen) writes: >I've been playing with MaxTransfer and Buffers, increasing and >decreasing the values. I've noticed very little, if any HD improvement. MaxTransfer is a limiting value. The higher it is, the faster the operation. Given a properly written driver, you do not have to set a MaxTransfer value, and it will transfer as much as it can, going as fast as it can. >I do notice that even setting both values at a minimum, I use 40K >per partition per drive. Is this normal? Two drives, each divided >into four partitions uses an incredible amount of RAM just by >mounting them. Partitions eat memory. If you have some solid reason for wanting to partition, and can afford the memory, by all means do so, but there I have only heard one valid reason to partition, and that is to reduce the time to recover should a partition bite the big one. Other than that, partitions are pretty much useless holdovers from the days when Intentionally Brain Munged machines couldn't handle large drives. -larry -- Frisbeetarianism: The belief that when you die, your soul goes up on the roof and gets stuck. +----------------------------------------------------------------------+ | // Larry Phillips | | \X/ lphillips@lpami.wimsey.bc.ca or uunet!van-bc!lpami!lphillips | | COMPUSERVE: 76703,4322 | +----------------------------------------------------------------------+