From: Don Whiteside (dwhite_at_shadow.net)
Date: Mon Feb 06 1995 - 13:28:31 EST
On Mon, 6 Feb 1995, Arne Helme wrote:
> Could someone please help me out with this one; Since IBM seems to
> have problems with the delivery of RAM cards to the thinkpads, I have
> been offered a replacement card from Kingston (either 8 MB or 16 MB).
> Is there anyone out there who has some experience with these cards?
> It seems that I'll be able to buy a 16 MB Kingston card for almost the
> same price as a 8 MB IBM card. This leads to my next question; are
> there any performance problems with running NetBSD on a thinkpad with
> more than 16 MB of RAM? I am not that familiar with the internals of
> these machines, but if I remember correctly, the performance of NetBSD
> degrades when the 16 MB RAM boundary is crossed.
I believe you're extrapolating outward from the fact that bus mastering
SCSI cards perform badly above 16M. Any bus mastering device in an ISA
machine (since the bus only has 16 bits for addressing) must use bounce
buffering. This makes it not as efficient as accessing the lower 16M of
memory.
GENERAL performance should not be effected. And since the TP uses IDE,
which is not a DMA device, this is not applicable.
========================================================================
Donald Alan Whiteside School of Computer Science
Official Usenet Dork for the week of Jan 9-13, 1995
GCS d-- -p+(---) l u+(-) e+ m+ s !n h f g+ w+ t+(++) r- y++
I am NSA of Borg: your private key will be assimilated.
========================================================================
This archive was generated by hypermail 2.1.3 : Thu Jan 23 2003 - 09:52:31 EST