Too much swap, how do I change it?

Question

I'm new at Ubuntu and I'm fiddling around with Ubuntu Server 14.04. I'm trying to get it to run a Minecraft server, but whenever anyone joins, it starts skipping ticks and players reported heavy block-lag.

I checked my RAM with free -m and got the following:

                 total      used     free     shared     buffers     cached
Mem:             1507        321     1886          0          17        194
-/+ buffers/cache:           109     1397
Swap:             7377         0     7377

The number that I need for my server is 1397. Other than that, a swap ratio of near 1:7 seems a bit much. My question is how I can change these numbers; turn the ratio to a 1:1 and increase my free -/+ (whatever -/+ means).

I'm sorry if this seems trivial to anyone, but I am an incredible noob and I refuse to use PuTTy as I want to learn all the commands. Thanks in advance!

[RE-EDIT] Upgraded 12.04 to 14.04. Bear with me here, people. Thanks in advance.

possible duplicate of How do I resize partitions using command line without using a GUI on a server? — A.B., Apr 25 '15 at 19:53
So I can't downsize my partitions online. But I would have no idea how to begin with making a swap file. I'll just use PuTTy and make everything a bit more "Windows". Sifting through directories is still a bit difficult since I know virtually zero commands and I'm used to having to click on icons rather than punch in commands. — Denzel Zaman, Apr 25 '15 at 21:48

score 0 · Answer 1 · answered Apr 25 '15 at 21:38

The Swap total given by free reflects the swap space configured on your system, which is the amount of space that the system can use on disk if the amount of RAM is insufficient. An overview on swap can be found at https://help.ubuntu.com/community/SwapFaq.

In the output you posted we can see that none of the swap is actually used, which means that the system has enough available RAM and doesn't need to page out any data to the swap space on the disk.

Reducing the available swap space won't help with any performance issues, it would just free up some more disk space.

The free output doesn't show any lack of RAM on your system, you have 1397 MB available for programs to use. I would guess that the problem lies either in CPU power or in networking issues. You could try to run top while the Minecraft server is running and post the content of the %Cpu(s) line to determine whether the CPU is the cause for the lag.

Alright, thanks! I'll try that. Right after I'm done installing the right Ubuntu version. Apparently, I was running 10.04. Mislabeled. But thanks in advance! — Denzel Zaman, Apr 25 '15 at 21:51

Too much swap, how do I change it?

1 Answers1