Player Character Ghosting (after player leaves game)

[So_1337]

I do it constantly. Granted, I don't know of any mob spawns in the Nexus =P

[Angelox]

I'm thinking if you are at the same IP of your server, you won't see any ghosting - you'll need people that log in from distant IPs and suddenly drop out.
Maybe some how this remains cached in the system and the server thinks there's someone still there, or maybe the server missed some packets with the sudden drop out.
could be they get LD on zoning, then the character arrives in the next zone, but the PC is gone.
Problem is, it's seems related to other players on your server. At one time, I remember having this problem when I ran a windows server. it was when I first started out. At the time I had a Pentium 3 with little memory and was playing on the server with the client on the same machine.
I remember seeing a lot of the ghosting effect. I figured it was related to lag , and lag created by multiple players zoning and logging in (LD).
I could play alone fine, but this would start when others logged in.
Also, I don't think this happens with multiple players on Minilogin - I think its related to the Public Login server.
Anyway, those were thoughts an ideas I had at the time, Went Linux and the problem for me ended with that. I still use a windows server for testing, but it's Minilogin, and I don't see any ghosting there.
You might want to try getting some friends to try you out on a Minilogin server.
Thing is, you can't have a solution until you can find what makes the problem, these are some things I'd try out, to see if anything were different.

Make observations when you see a ghosted character;
was it static or dynamic zone? was he zoning ? did he log? (you can find the account by the ghosted character name). See if you can find a pattern somewhere.

[paaco]

Seems like on my server I find myself ghosting a lot. Playing from the same machine the server is located on. It is on a static zone and happens if I right click EQ on the taskbar and close it out like that.

All it shows in the logs is:

[09.19. - 23:52:28] Starting Log: logs/eqemu_error_zone_1300.log
[09.19. - 23:52:28] Ghosting client: Account ID:1 Name:paaco Character:Paaca IP:192.168.1.3

[trevius]

The problem happens most commonly if people /quit or /exit, or if they go LD, but I am pretty sure it even has a rare chance to happen if they /camp. On a public server when I was running Windows, I would commonly see up to 15 or more ghosted characters in nexus at any given time of the day if I didn't boot them out manually every few hours or so.

The easiest way to tell 100% if a character is a player ghost is to turn on inspect so you can inspect people "/toggleinspect on" (you can test by inspecting yourself or another player you know isn't a ghost) then try right clicking a suspected ghost player and if the inspect window doesn't pop up, they are sure to be a ghost.

Even after they log off, you will continue to get net error messages from them in the log files. I believe the error that shows up is something like this:

Tried to write a packet beyond the end of the queue!

The error starts with showing incremented packet numbers, but eventually I think it just shows the same packet number over and over and over. And that error will continue to flood server logs even after the player has logged off and I think even after you #kick the ghosted character. So, it is like a connection isn't being brought down for some reason even if there is no connection. I think I have even had a player reboot their PC and it didn't stop the errors or disconnect the ghosted character. So, to me it seems like the issue may be that the server is just hung in some sort of loop.

More info on that log error can be seen in this post:

http://www.eqemulator.net/forums/sho...light=flooding

[KLS]

I don't get the packet flood with ghosting players. It's something with the netcode isn't timing out connections for windows in the zone server.

[trevius]

After reading through that post I linked above again, I notice that the error that seems to be generated when this problem occurs seems to be coded here:

EQStream.cpp

if(CompareSequence(NextOutSeq, seq_send) == SeqFuture) {
_log(NET__ERROR, _L "Tried to write a packet beyond the end of the queue! (%d is past next out %d)" __L, seq_send, NextOutSeq);
sitr=SequencedQueue.end();
continue;
}

And, looking into what that piece of code does, I looked at CompareSequence and SeqFuture so far. Here is the code for that command and I noted a part in RED that I think might be a mistake:

//returns SeqFuture if `seq` is later than `expected_seq`
EQStream::SeqOrder EQStream::CompareSequence(uint16 expected_seq , uint16 seq)
{
	if (expected_seq==seq) {
		// Curent
		return SeqInOrder;
	}  else if ((seq > expected_seq && (uint32)seq < ((uint32)expected_seq + EQStream::MaxWindowSize)) || seq < (expected_seq - EQStream::MaxWindowSize)) {
		// Future
		return SeqFuture;
	} else {
		// Past
		return SeqPast;
	}
}

I think that line might need to be removed and replaced with this:

	}  else if (seq > expected_seq && (uint32)seq < ((uint32)expected_seq + EQStream::MaxWindowSize))  {

That should label all packets that are lower than the expected sequence as SeqPast. It will also label any any packets that are above the MaxWindowSize as SeqPast. And, if an ack is set as SeqPast, it should always SendOutOfOrderAck, which means it should correct most out of order issues I think.

Here is the MaxWindowSize setting code:

uint16 EQStream::MaxWindowSize=2048;

I will try to get the minor change noted above in and tested on my server and see if anything funky starts happening or if it has any noticeable effect. But, since I only run a Linux server, I won't see player ghosts anyway, so it might be pointless for me to test it. But, as long as it doesn't break anything, I could always update it in the new SVN and when Cavedude builds the Win32 binaries, windows servers could easily start testing and see what happens if anything.

Just from reading through the EQStream.cpp file, to me it looks like they are doing some sloppy stuff and maybe some extra work that isn't really needed. But, I am definitely no expert or anywhere near as skilled as the people who originally wrote that file. It seems like we could just check if an ack is in order and if not then always send an OutOfOrder ack. Maybe if we play with this file for a while, we can get most or all network issues worked out.

[KLS]

A lot of what goes on isn't because we want to do it that way. The client controls the netcode and we don't control the client. =p

[trevius]

Ya, but if we are getting out of order acks, doesn't that mean something is messed up and the server needs to compensate for it to recover properly? Obviously it is working for the most part or there would be more issues. But, I think a couple little tweaks could help resolve some of the issues like hung sessions, out of order acks, and whatever is needed to fix the Windows player ghosting issue.