Questions about : auto reboot - Nb ram free -

Hello,

I’m using Mineos since a year, and i get a couple of questions about the interface .

First, how work the auto reboot feature ?
I have a server running (100% functional) and i don’t want to try something i’m not fully understanding. If i choose an restart_interval of 24 hours, when will the server reboot ? At 00:00, or 24h after he start ? Shall i have any way to choose the effective reboot time ?

Next, my question is about the Free ram count in the interface.
I’m using MINEOS on a ESXI virtual machine with 8Go of RAM. There is 4Go for my minecraft server, 2Go for an tmpfs directory (my minecraft map directories use 700Mo). This is different views i got for the free RAM left :

  • MINEOS GUI tell me only 161Mo RAM Left !!
  • Webmin tell me there is only 2.8Go used.
  • Linux “Free” command : 8Go used and only 150Mo free …
  • Linux “Nmon” (small bash interface which help me to monitor my resources) give me same as “Free” and precise : Cached= 4882.8 Active= 3919.7.

I’m just asking : where is my free RAM ? :smile:

Thank’s for your help.

MineOS doesn’t have an auto-reboot feature for your box, but it does have a scheduled interval restart for your game servers.

restart_interval is only one method of restarting your server. It allows you to enter a value which (in seconds) corresponds to how frequently you want the server ‘stop’-ped and then restarted.

The method is measured in minutes since midnight, so putting in ‘1440’, it will restart once per day at 0:00.

If you put in 720, it will restart twice per day at 0:00 and 12:00. Likewise 1440 / 6 = 240 = 6 restarts a day, every 240 minutes (4 hours).

Many people don’t like the lack of precision “i want to restart at this time X and Y”. This is possible through the use of crontabs, which is distro-specific. Some distros use crontabs, some don’t (“at” command, etc). As a result, MineOS cannot be made to configure crontabs for a user, it is up to the user to do it manually.

This is where mineos_console.py comes in, as it is the command line way to do MineOS functions without being at the web-ui. You could create a bash script, for example, that does the following things:

[./myscript.sh]

cd /usr/games/minecraft
./mineos_console.py -d /var/games/minecraft stop
sleep 20
./mineos_console.py -d /var/games/minecraft start

This is a rudimentary example of a restart script (you’ll want to tune it much better to match your sleep time to your shutdown time + some buffer). This server can be run as root and if it works, it can then be applied to your servers via crontabs, which your distro will provide instructions for.

100% of the time, trust the values of the command line or your virtual machine utilities. MineOS uses a very naive mechanism (polls the /proc filesystem) and reports free memory. Of course, the free memory value it reports is one of many memory values that different utilities can pull from.

MineOS uses /proc’s “meminfo”/“MemFree”. WebMin might be using something different, ‘free’ might report something different, nmon–you get the idea. The MineOS value is entirely reliable–for getting the MemFree value. If you see other values it’s probably reporting something that is taking into account unused pages of memory, cache, etc. This is further obfuscated when you’re using ESXI VMs. Do you know if your VM manager is reporting memory actually used in relation to the host system? Or do you know if its reporting used memory in relation to the VM? I can’t know, but your VM suite should probably be able to explain it better than I.

That aside: is there a reason to be concerned about your memory?

Are you experiencing actual memory issues or do you just want the ‘free memory’ number higher? Keep in mind, unused memory is…potentially not useful. Are you expecting bursts of usage from other parts of your system that need that memory?

In other words, why do you “want” more free RAM?

Thank’s for your two perfect replies.

Concerning the reboot system i should have to precise that i had understood it only concern the minecraft server.
I aiming with this procedure to reboot the server early in the morning for cleaning the RAM usage.
May could you as a future evolution of MINEOS, allow us to precise the exact server reboot time ?

I’m not getting any troubles with the low RAM available because as you said i think it’s not reflecting the real usage of this resource. To defend my point of view, ESXI show me the real usage of the RAM for an virtual appliance, and as expected it’s lower than the linux system said (pretty reassured).

I’m actually thinking about making a full feedback of my minecraft server running on ESXI 5.5 with an casual home made server. And the way i choose to use RAM (TMPFS) for loading the server MAP and the mechanism who save and restore this data at startup or each 10 minutes. And also the fact that this server is running from an SSD drive since 6 months without destroying them (as i could read it sometime). Secondarily, i’m also using overviewer on a separate linux distro to generate an daily minecraft “google” map of my server.

Do you think it could be useful for the community ?

Thank’s again for taking care of your proud MINEOS users ! And well played from the work you’ve done (and you’re doing!) on it. I could not imagine running an 24/7 minecraft server without MINEOS to managed it !

Have a nice day.
(French user of mineos :smile: , it will explain my poor english or not ?)

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