Re: slow internet in DOSBox but not on host machine

Posted on 2021-06-10, 22:43

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by mbbrutman

in DOSBox Games/Apps

in DOSBox Games/Apps

It's hard to follow through all of that. If you are developing a program using the mTCP TCP/IP code, then I would use a virtual machine that emulates a real Ethernet card. I love DOSBox, but it's lack of Ethernet emulation means that you have to futz with the SLIP or PPP configuration, and that is …

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Re: slow internet in DOSBox but not on host machine

Posted on 2021-06-09, 21:26

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by mbbrutman

in DOSBox Games/Apps

in DOSBox Games/Apps

That mTCP is 6 years old already. The newest version was released in March 2020, and there were significant fixes to htget. On your speed problem ... I'm not sure how DOSBox models the serial port, but if it is actually doing it in a timing accurate manner then 9600 bps is going to be pretty slow. …

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Re: RTL8139 works in Win98SE, but unreliable in DOS (or DOS mode)?

Posted on 2021-05-30, 19:26

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by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Your are bumping into a common problem with device drivers ... to be on the safe side a device driver should reset the device before touching it, and should assume that nothing is correct. The DOS packet driver is probably not doing that because the poor junior-level programmer who is assigned to …

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Re: PCI NIC packet driver performance / speed

Posted on 2021-03-17, 19:27

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by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

My P133 with a 100Mb/sec PCI card is hitting around 10.4MBytes/sec, which is similar to what your machines are getting. You are getting with 15% of wire speed and there is TCP/IP packet overhead too, so it is not going to get much faster. Keep in mind that real programs do useful things ... SPDTEST …

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Re: PCI NIC packet driver performance / speed

Posted on 2021-03-17, 03:42

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by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Yeah, I'm good but I don't do support for the WATTCP stuff. ;-0

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Re: PCI NIC packet driver performance / speed

Posted on 2021-03-16, 22:49

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by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Even just starting with DEBUGGING=1 is a good start - that captures just warnings and errors. Going to DEBUGGING=0x7F (or 127 for us humans) is if I need to debug things at a deeper level. Email me when you are ready. I'm not going to add recursive gets or puts anytime soon - it's too much of a pain …

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Re: PCI NIC packet driver performance / speed

Posted on 2021-03-15, 21:23

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by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

There is a previous thread here you should read where the machine was suffering from packet drops due to a misconfiguration. You should read the debugging section of the mTCP PDF, generate a trace, and send me to me. Most of the time it's a problem with the machine or the network.

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-26, 01:44

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by mbbrutman

in Milliways

in Milliways

Wrapping this up ... I had a small bug, but fixing it had no effect because it wasn't the root of the problem. If you are running a shim to make an ODI driver look like a packet driver you should specify an MTU of 1500. With the default MTU of 576 many more packets were being generated, and it was …

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Re: Making DOS 6.22 recognize all extended memory

Posted on 2021-02-23, 21:02

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by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I don't think CGI is that much of a security problem. The EXE that gets called is pre-registered ahead of time. And it should be passed a 'context' object, so that it can make the appropriate decision about permissions and security. It's not anywhere near as bad as running Telnet to access your …

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Re: Making DOS 6.22 recognize all extended memory

Posted on 2021-02-23, 20:06

by

by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

mTCP HTTPSERV doesn't have CGIBIN type capability because there is no guarantee that the program you call out to will return quickly enough to avoid dropped packets. If you have one or two connections open and active and one of them calls out to an EXE program, you are going to kill the other …

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-22, 21:12

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by mbbrutman

in Milliways

in Milliways

Just a quick update ... Grzyb and I are still debugging, but one of the problems I found is his MTU size. He was using the default MTU which is 576, when 1500 is optimal for Ethernet. MTU is specified in the mTCP CFG file, so if you have not set it then you are using the default of 576. Larger MTU …

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-18, 16:57

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by mbbrutman

in Milliways

in Milliways

Ok, well clearly that bug isn't the cause of your pain. (The debug log showed the same excessive number of missed packets.) There were not many changes to the TCP layer and below between 2015 and 2020. The window resizing code was added and was pretty extensively tested, but even then it still has …

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-18, 03:08

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by mbbrutman

in Milliways

in Milliways

Grzyb, I started digging through the code and I noticed a bug that might be responsible for what you are seeing. Try this, and if it works, then I'll tell you what I screwed up. (And then fixed ...) http://www.brutman.com/mTCP/ftp_flowcontrolfix.exe (I can't click on the link to start the download, …

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-17, 16:58

by

by mbbrutman

in Milliways

in Milliways

Well, that theory did not pan out ... you don't have the same level of dropped packets in the 2015 code. It actually is running quite nicely; 28 errors, not 2900+ ...

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-17, 02:36

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by mbbrutman

in Milliways

in Milliways

Grzyb, In 2019 I added code to improve the flow control on noisy/lossy connections. That code shrinks and grows the TCP receive window size depending on how many packets are being lost. Without this code connections would often just freeze and die because the two sides would get so far apart that …

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-17, 02:06

by

by mbbrutman

in Milliways

in Milliways

FTPSRV is not be affected by the change to use the BIOS calls for updating file transfer progress.

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-02-16, 20:53

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by mbbrutman

in Milliways

in Milliways

Interesting, but I suspect it is related to your packet driver setup. On my 386-40 I get the following: 2015 code: 526.3 KB/sec sending and 543.6 KB/sec receiving 2020 code: 464.5 KB/sec sending and 485.2 KB/sec receiving (All tests are with a 16K TCP buffer and a 16K file buffer) So it is slower, …

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Re: What retro activity did you get up to today?

Posted on 2021-02-01, 00:54

by

by mbbrutman

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I'm about a week late with this update ... I purchased another IBM PC Compact printer from eBay to have another spare. For those of you who are not familiar with it, it is a small serial printer running at 1200 bps that prints on fax paper. The print quality is atrocious but it never needs ribbons, …

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2021-01-06, 06:20

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by mbbrutman

in Milliways

in Milliways

Pierre32 - thank you. It has been a great project and I'm happy that people are enjoying it.

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Re: A new mTCP is available! (version 2020-01-01)

Posted on 2020-12-30, 18:45

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by mbbrutman

in Milliways

in Milliways

What is the scope of mTCP? I chose TCP/IP because it is the open protocol of choice for any machine to use. It is not just about simple printer and file sharing. Telnet and FTP can take you anywhere the Internet is, no matter what that machine is. You can choose to use it on your own home network or …

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