docker out of memory - docker

Question

I'm new to docker and have a problem with existing scripts that work on one machine but not on another. I'm willing to read documentation and existing answers but am a little lost on the many levels of abstraction in this topic.
Running an application in docker results in an out of memory exception. I start docker with --ulimit memlock -1:-1 and no other limit on memory seems to be applied.
df -h inside docker yields
root#localhost:/# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/docker-253:0-1312128-9219e5dbff0bc6da3a663fab31ec34e6f6b28ba6c8fbd3b343d9131d41f6b1c9 10G 3.0G 7.1G 30% /
tmpfs 3.9G 0 3.9G 0% /dev
tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup
/dev/mapper/fedora-root 50G 20G 28G 42% /etc/hosts
/dev/mapper/fedora-home 401G 151G 231G 40% /var/results
shm 64M 0 64M 0% /dev/shm
When the OOM occurs, the first file system is used to 95%. Where does this limit 10G come from? Where could I adjust it?
All partitions of my device surely have enough free space.
[uscholz#localhost RegressionTesting]$ docker info
Containers: 2
Running: 1
Paused: 0
Stopped: 1
Images: 52
Server Version: 1.10.3
Storage Driver: devicemapper
Pool Name: docker-253:0-1312128-pool
Pool Blocksize: 65.54 kB
Base Device Size: 10.74 GB
Backing Filesystem: xfs
Data file: /dev/loop0
Metadata file: /dev/loop1
Data Space Used: 12.17 GB
Data Space Total: 107.4 GB
Data Space Available: 32.16 GB
Metadata Space Used: 7.889 MB
Metadata Space Total: 2.147 GB
Metadata Space Available: 2.14 GB
Udev Sync Supported: true
Deferred Removal Enabled: false
Deferred Deletion Enabled: false
Deferred Deleted Device Count: 0
Data loop file: /var/lib/docker/devicemapper/devicemapper/data
WARNING: Usage of loopback devices is strongly discouraged for production use. Either use `--storage-opt dm.thinpooldev` or use `--storage-opt dm.no_warn_on_loop_devices=true` to suppress this warning.
Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
Library Version: 1.02.122 (2016-04-09)
Execution Driver: native-0.2
Logging Driver: journald
Plugins:
Volume: local
Network: bridge null host
Kernel Version: 4.8.12-200.fc24.x86_64
Operating System: Fedora 24 (Twenty Four)
OSType: linux
Architecture: x86_64
Number of Docker Hooks: 2
CPUs: 8
Total Memory: 7.787 GiB
Name: localhost.localdomain
ID: YXHN:34PG:ZQA3:P4DU:4TFY:6THC:VFI2:E7BE:IGOW:2TTH:3BS7:3OOD
Registries: docker.io (secure)

Answer 1

Where does this limit 10G come from?
It comes from dockerd (daemon) which create special 'device' 10G size by default for new container
Where could I adjust it?
You can set it by providing --storage-opt dm.basesize=50G to dockerd is case of devicemapper storage driver
P.S.: actually, OOM not cause of disk space, but memory, i think
And there are two possible reasons:
you out of real memory. Than use free -m on docker host machine to watch it. Container use the same memory as host with docker
you out of shared memory. Not sure about OOM, but docker set /dev/shm to 64M by default. It is not appropriate for some applications