Newsgroups: bit.listserv.novell
Date:         Thu, 13 Aug 1992 16:16:51 EDT
Reply-To:     Novell LAN Interest Group <NOVELL@SUVM.BITNET>
From:         "J. Pilant" <pilant@NADC.NADC.NAVY.MIL>
Subject:      re: Windows local permanent swapfile (or temporary?)
X-To:         NOVELL%SUVM@pucc.PRINCETON.EDU

James Nash <ccx020@CCK.COVENTRY.AC.UK> writes:
>These machines now have room for a large swapfile and all those gorgeous
>temporary files Windows loves to create. I assumed that it would be best to
>create a permanent swapfile on the hard disk and let the networked copy pick
>it up.  [N.B. We run Windows from the network by keeping the INI & GRP files
>for each user in their own MAP ROOTed home directory and adding a search path
>to the main shared Windows directory on the network. BTW we use Novell 3.11]
>
>Would I be better off letting Windows create a temporary swapfile on the hard
>disk at startup? My opinion is that the permanent one is stored in contiguous
>space and therefore likely to be much faster. Addmittedly, if you start using
>the SWAPFILE you have already hit the performance bucket but some of our
>machines are still 2 Meg waiting for an upgrade.
>
>Having decided to have permanent swapfiles on these machines, I came to
>delete the local version of Windows which had laid dormant for a couple of
>months on one of these machines. Windows on the network no longer picked up
>the swapfile on the hard disk however many times I deleted it and re-created
>it. I traced this down to SPART.PAR being non-existant (I deleted it when I
>deleted the local Windows directories and was erasing it on the network).
>
>SPART.PAR points to the location and name of the permanent swapfile
>(C:SPART.PAR) but does it also point to the start and end sectors on the
>hard disk? i.e. is it used to bypass the FAT?
>
>The reason I ask is that the solution to my problem invloves either creating
>a system-wide SPART.PAR and copying it to everyone's home directory on the
>network, or creating a SPART.PAR on the local machine and copying that up to
>the user's directory every time Windows is run. (exact procedure below) The
>reason for erasing and copying each time is that the same user may go and use
>a different machine where the swapfile is located in a different place.
>
>Which is technically best? I know the latter is a pain in that it means
>keeping *another* system file locally.

First, the theory of windows swap files:
none: create temp file when more memory is needed.
temp: allocate via dos a given amount of space accessed by dos.  Guarenteed
compatibility accross disk types.
perm: allocate via dos a given amount of space accessed directly and avoid
delays caused by the use of dos.  This requires knowledge of the sectors used
and is very disk drive specific.

Second: the SPART.PAR file
This file apparently stores the sector numbers used by the perm file, and so
is machine specific.  As to storing a *system* file on the local machine,
what is the *swapfile* if not a system file?  If you want to store the file
on the server, you must copy the machine (not user) specific file.  While the
ethernet number looks good for uniqueness, it fails because the card may not
stay with the disk.

Third: my recommendation
I suggest you use a temp swapfile.  Allocating a perm file will be recorded
in the windows setup, and you must have it on all disks.  With a temp
swapfile, windows will create it if it is not there.  As to access times, if
the application swaps to disk, the additional delay of dos will be a very
small delay.  A disk cache may help here.

/jeff
Comments: Gated by NETNEWS@AUVM.AMERICAN.EDU
Subject: (no subject given)