[Simh] Ultrix network issues

[Douglas Hall]

On Thu, 15 Nov 2018, at 17:25, Mark Pizzolato wrote:

> From what you've said here, not being a Xen user myself, it is not 100% clear 
> exactly what's running where.
> 
> Is it: Ultrix on simh running on Debian Stretch running under Xen?
> OR:  Ultrix on simh running on Xen running under Debian Stretch?
> OR: Something else...?

Sorry if that wasn't clear.  I have a Xen environment running with Debian Stretch in Dom0 and also in the DomU that has simh running.  

> 
> Without regard to that, if you:
> 1) Stop the VMS instance running under your configuration
> 2) Stop the Ultrix instance running under your configuration
> 3) Change the Ultrix's configuration file to attach the VMS instance's 
> boot disk image
> 4) Start simh with the otherwise unchanged Ultrix configuration 
> 5) Confirm that networking with the VMS OS running in the simh Ultrix 
> simulator is absolutely normal or if it exhibits issues similar to the 
> Ultrix OS's behavior.

No change. network performance with VMS is as expected, performance with Ultrix is unusable.  I can attach a pcap of a file transfer to the Ultrix system if it helps.

As a further test, I installed NetBSD8/vax in simh on the same DomU I have Ultrix on and it doesn't exhibit any unusual issues with network performance.

For reference, here is the  show version

MicroVAX 3900 simulator V4.0-0 Current
    Simulator Framework Capabilities:
        64b data
        64b addresses
        Threaded Ethernet Packet transports:PCAP:TAP:NAT:UDP
        Idle/Throttling support is available
        Virtual Hard Disk (VHD) support
        RAW disk and CD/DVD ROM support
        Asynchronous I/O support (Lock free asynchronous event queue)
        Asynchronous Clock support
        FrontPanel API Version 12
    Host Platform:
        Compiler: GCC 4.2.1 Compatible Clang 3.8.1 (tags/RELEASE_381/final)
        Simulator Compiled as C arch: x64 (Release Build) on Nov 10 2018 at 16:37:50
        Memory Access: Little Endian
        Memory Pointer Size: 64 bits
        Large File (>2GB) support
        SDL Video support: No Video Support
        RegEx support for EXPECT commands
        OS clock resolution: 1ms
        Time taken by msleep(1): 1ms
        OS: Linux ermine-xen 4.9.0-8-amd64 #1 SMP Debian 4.9.130-2 (2018-10-27) x86_64 GNU/Linux
        git commit id: acbea915
        git commit time: 2018-11-10T04:34:43-0800

-Douglas