Driver plugin framework to facilitate development of driver plugins.
Implementing plugins only need to implement the DriverPlugin interface.
The framework proxies this interface to the go-plugin GRPC interface generated
from the driver.proto spec.
A testing harness is provided to allow implementing drivers to test the full
lifecycle of the driver plugin. An example use:
func TestMyDriver(t *testing.T) {
harness := NewDriverHarness(t, &MyDiverPlugin{})
// The harness implements the DriverPlugin interface and can be used as such
taskHandle, err := harness.StartTask(...)
}
* client/executor: refactor client to remove interpolation
* executor: POC libcontainer based executor
* vendor: use hashicorp libcontainer fork
* vendor: add libcontainer/nsenter dep
* executor: updated executor interface to simplify operations
* executor: implement logging pipe
* logmon: new logmon plugin to manage task logs
* driver/executor: use logmon for log management
* executor: fix tests and windows build
* executor: fix logging key names
* executor: fix test failures
* executor: add config field to toggle between using libcontainer and standard executors
* logmon: use discover utility to discover nomad executable
* executor: only call libcontainer-shim on main in linux
* logmon: use seperate path configs for stdout/stderr fifos
* executor: windows fixes
* executor: created reusable pid stats collection utility that can be used in an executor
* executor: update fifo.Open calls
* executor: fix build
* remove executor from docker driver
* executor: Shutdown func to kill and cleanup executor and its children
* executor: move linux specific universal executor funcs to seperate file
* move logmon initialization to a task runner hook
* client: doc fixes and renaming from code review
* taskrunner: use shared config struct for logmon fifo fields
* taskrunner: logmon only needs to be started once per task
* vendor: bump libcontainer and docker to remove Sirupsen imports
* vendor: fix bad vendoring of archive package
* vendor: fix api changes to cgroups in executor
* vendor: fix docker api changes
* vendor: update github.com/Azure/go-ansiterm to use non capitalized logrus import
Sending the Ctrl-Break signal to PowerShell <6 causes it to drop into
debug mode. Closing its output pipe at that point will block
indefinitely and prevent the process from being killed by Nomad.
See the upstream powershell issue for details:
https://github.com/PowerShell/PowerShell/issues/4254
This commit changes the force closing of the stdout/stderr file
descriptor from closing immediately to being closed after a grace
period. This allows the created process to close its own file and allows
copying of the data.
A comment in the nomad source code states that swapping for
executor_linux allocations is disabled but it wasn't.
Nomad wrote -1 to the memsw.limit_in_bytes cgroup file to disable
swapping.
This has the following problems:
1.) Writing -1 to the file does not disable swapping. It sets
the limit for memory and swap to unlimited.
2.) On common Linux distributions like Ubuntu 16.04 LTS the
memsw.limit_in_bytes cgroup file does not exist by default.
The memsw.limit_in_bytes file only exist if the Linux kernel is
build with CONFIG_MEMCG_SWAP=yes and either
CONFIG_MEMCG_SWAP_ENABLED=yes or when the kernel parameter
swapaccount=1 is passed during boot.
Most Linux distributions disable swap accounting by default because
of higher memory usage.
Nomad silently ignores if writing to the memsw.limit_in_bytes file
fails. The allocation succeeds, no message is logged to notify the
user.
To ensure that disabling swap works on common Linux kernels, disable
swapping by writing 0 to the memory.swappiness file.
Using the memory.swappiness file only requires that the kernel is
compiled with CONFIG_MEMCG=yes. This is the default in common Linux
kernels.
Nick Ethier