Optimizing Debian for Java, what should be done and how?

Question

linux

Everyone knows that Java is not the most pleasant guest on any server. I had a question, because there are game hosting sites that host hundreds of the same Minecrafts, how is this even possible, taking into account the consumption of Java resources?
I recently started administering a machine on which I conduct various tests. So if this is a stupid question, sorry.

Answer 1

Java optimization is a strange thing. It is not Java that needs to be optimized for Debian (let Oracle do it).
Optimize exactly the minecraft server. And there is something to optimize)

Answer 2

usually two people play this minecraft, so it's not surprising.
It all depends on the number of people in the game, no matter how many minecraft you have launched, the overall online is important.
global optimization will not work, you need a lot of memory, a lot of processors.

Answer 3

I can say that the minecraft server (bukkit family) cannot be launched in large numbers without virtualization. The peculiarity of minecraft is that it runs in one thread on 1 core, all running copies. Most cut the server into virtual machines by 1 core, if there are gluttonous ones, another 1 core is allocated. For virtualization, the most optimal in this case is kvm or hyper-v, xen works fine with some features. OpenVZ doesn’t fit in any way (maybe I screwed up here), because on all the hostings that I tried, the server ate all the RAM and was killed by the provider, when exactly the same build with a similar load worked fine with a reboot every night. For a minecraft server with 20-30 plugins, 30-70MB of RAM per slot is the norm, so don't be scared if anything. It is also preferable to take an ssd. the server is not written very rationally and constantly pulls the hard drive, regular sata will only work if you are alone on this drive, I have not tried sas for servers on a separate machine. Special server optimizations can give ~2 slots, which is not worth the time. The only "optimization" option is a ramdisk, but problems with the possibility of data loss and crap with a constant backup of this will kill all the pluses. The server constantly writes something to the world files, if there is a player there, the size of the world (~ 150mb) does not allow making a normal backup. All this is personal experience and if there are errors / suggestions - write. The only "optimization" option is a ramdisk, but problems with the possibility of data loss and crap with a constant backup of this will kill all the pluses. The server constantly writes something to the world files, if there is a player there, the size of the world (~ 150mb) does not allow making a normal backup. All this is personal experience and if there are errors / suggestions - write. The only "optimization" option is a ramdisk, but problems with the possibility of data loss and crap with a constant backup of this will kill all the pluses. The server constantly writes something to the world files, if there is a player there, the size of the world (~ 150mb) does not allow making a normal backup. All this is personal experience and if there are errors / suggestions - write.