server crash/freez every 40 minutes

[Slind]

Hey,

our server freezes every ~40 minutes with out any crash-report and the consol just stops to write. So the server also wont start with autorestart after crash. Its like it just freezed.
What can i do to find the source ?

Running:
Mindcrack 8.2
MPPC+ 244
Plugins:

Lightvote​

WorldEdit​

Buycraft​

ZavautoMessager​

PermissionsEx​

Multiverse-Core​

Stats​

Prism​

Essentials​

EssentialsProtect​

EssentialsSpawn​

Multiverse-Portals​

Multiverse_Inventories​

EssentialsChat​

EssentialsAnitBuild​

 

[Naolas]

Is anyone using rednet/modem from computercraft?

There are issues with deadlocks there, especially with turtles.

 

[Slind]

i think so. Does this mean the server freezes when the chunk where the turtle is, is loaded, or when they work. and is this only there when multiverse-Core is enabled ?

 

[Naolas]

It has a chance to happen when they send messages. It appears to happen much more frequently with turtles than with computers.

If you want to make sure it never happens, I fear you will have to tell your users to not use it for now.
If you are fine for it to rarely happen, ask them to not use rednet with turtles only.

It's a long long existing bug. If you are motivated you can try reporting it (again).

 

[Slind]

k, thanks
but is there a connection to multiverse, because if i disable it, it never happens

 

[Naolas]

The server I run doesn't use multiverse. It could just be coincidence that people started using rednet/modem when you added it? Or it may be another issue altogether.

Abdiel, who plays on the server, does alot with rednet and replicated it without problem in a single player world. He keeps up to date with this particular bug and tested that it happens much quicker with turtles. The bug has been addressed before and was supposedly fixed.

Since we replaced all turtles with computers we only had one freeze, so it is hard to say if that was a fluke and unrelated, or if it only very rarely happens.

How much control do you have over your server? I use a cron script to periodically check if the server is responding and restart it if that is not the case.

 

[Slind]

at the provider where the server is running the only thing i have are the logs

 

[Naolas]

A way to test if it is computercraft would be to rename all startup files to something else, so that no computer is running code after the server restarts. If that wasn't the case, you can rename it back later.

On linux you would do something like this:

find -name startup -exec mv {} startup_backup \;

 

[Slind]

k, but the only thing i can do is to rename the mod.jar of computercraft.

 

[Naolas]

That won't do anything (the name of the jar files does not matter). You could remove computercraft alltogether, but that WILL DELETE everything computercraft related permanently. I highly advise against that.

Do you have access to config files? You could disable chunkloading and reenable it once you talked to people to let them know to not run rednet/modem code for now.

 

[Slind]

which config file ?

the only thing i have is a ftp acc to the server files

 

[Naolas]

Oh, that's great. Then you do have access to all the computercraft files.

You can find them in wolrd/computercraft. Depending on how many folders you find there, you could rename the startup files by hand.

Chunkloading is spread out over different files, and is on second thought not that easy to disable/reenable (I think you would destroy turtles with chunkloader upgrade).

crailcraft/modules.cfg
ChickenChunks.cfg
StevesCarts.cfg
MiscPeripherals.cfg

 

[Slind]

ohhh

 

[Naolas]

Just a quick workaround idea how to disable the modems easily:

I managed to start my server by setting all the wireless modem ranges to zero in the config file.

Another attempt to bring attention to this issue (incase anyone wants to add some info).
http://www.computercraft.info/forums2/index.php?/topic/11525-a-busy-rednet-causes-deadlocks/

 

[Slind]

thanks

do i missed one ?


# The range of Wireless Modems at maximum altitude in clear weather, in meters
I:modem_highAltitudeRange=384

# The range of Wireless Modems at maximum altitude in stormy weather, in meters
I:modem_highAltitudeRangeDuringStorm=64

# The range of Wireless Modems at low altitude in clear weather, in meters
I:modem_range=64

# The range of Wireless Modems at low altitude in stormy weather, in meters
I:modem_rangeDuringStorm=16

 

[Naolas]

I think those are the ones. If you set those to 0 and you still get the deadlocks, then it is something else.

Good luck.

(let your users know, so they don't spend hours trying to figure out why rednet isn't working )

 

[Slind]

it worked, thank u so much