swapoff failed: Cannot allocate memory

Question

Server's Output shows the following:

 # free -h
             total       used       free     shared    buffers     cached
Mem:          7.7G       7.6G       123M       156K       1.8M       248M
-/+ buffers/cache:       7.3G       373M
Swap:           9G       4.9G       5.1G

I tried to turn off the swap but unable to do so!

#swapoff /dev/dm-1
swapoff: /dev/dm-1: swapoff failed: Cannot allocate memory

Then, to resolve this problem, I did:
Step 1: I tried to create a new swap file: /home/swap of 2G Size:

# dd if=/dev/zero of=/home/swap bs=1024 count=2097152
# mkswap /home/swap
# swapon /home/swap

**Step 2:**I tried to disable main swap since I have created a new swap file: /home/swap (But again getting error)

# swapoff /dev/dm-1
swapoff: /dev/dm-1: swapoff failed: Cannot allocate memory

When I tried to look whether new swap file created is actually using swap: It showed nothing! why??

# swapon -s
Filename                                Type            Size    Used    Priority
/dev/dm-1                               partition       8388604 5129864 -1
/home/swap                              file            2097148 0       -2

Any solution to the above problem?

Solution

You do not have enough RAM. Your machine is surviving because you use a swap file (i.e. using your hard drive for extra pseudo-RAM) but that is not supported by Kubernetes so it tried to turn that off which failed because you don't have enough RAM.

Comments

[Admin]

On your swap partition 4.9 GB are used. How do you suppose those 4.9 GB should fit in the 123 MB memory or 2 GB swap file you created? Why do you want to turn off the swap partition in the first place? The solution would be to add more ram or to reduce the load.