Re: Checking out src with Mercurial

[Chris Hanson <cmhanson%eschatologist.net@localhost>]

On Jun 20, 2020, at 3:06 PM, Johnny Billquist <bqt%update.uu.se@localhost> wrote:
> 
> On 2020-06-20 18:52, Dave McGuire wrote:
>>> On 6/20/20 5:01 AM, Holm Tiffe wrote:
>>> Great. ..and how many VAXen do have 128Mbytes of RAM?
>>   We have several VAXen at LSSM that have 128MB of RAM or more.  One of
>> them, a VAX-7000, has 1.5GB. :)
> 
> So do we at Update. But let's face it. It's a very small minority of machines (VAXen) that can have that much memory. And I don't think anything desk sized ever could.

I think you could, in theory, on a system with TURBOchannel or an equivalent expansion bus, by making a memory card and then somehow getting the OS to use the extra memory.

You might be best off writing a storage driver and using such a card as swap though, as it may be slower than main memory while still being orders of magnitude faster than a disk.

That and RAM disks are how NuBus memory cards in Macs were generally used: They were directly mapped, but it wasn’t straightforward to tell the OS to use the memory, and it’s on the other side of a bus with more overhead than main memory anyway.

  — Chris