diff options
| -rw-r--r-- | libpod.conf | 8 | ||||
| -rw-r--r-- | libpod/oci.go | 22 | ||||
| -rw-r--r-- | libpod/runtime.go | 32 |
3 files changed, 42 insertions, 20 deletions
diff --git a/libpod.conf b/libpod.conf index cc4a10cff..dcfeb67cc 100644 --- a/libpod.conf +++ b/libpod.conf @@ -80,3 +80,11 @@ pause_image = "k8s.gcr.io/pause:3.1" # Default command to run the pause container pause_command = "/pause" + +# Determines whether libpod will reserve ports on the host when they are +# forwarded to containers. When enabled, when ports are forwarded to containers, +# they are held open by conmon as long as the container is running, ensuring that +# they cannot be reused by other programs on the host. However, this can cause +# significant memory usage if a container has many ports forwarded to it. +# Disabling this can save memory. +#enable_port_reservation = true diff --git a/libpod/oci.go b/libpod/oci.go index e1c0d1261..3838394cb 100644 --- a/libpod/oci.go +++ b/libpod/oci.go @@ -66,6 +66,7 @@ type OCIRuntime struct { socketsDir string logSizeMax int64 noPivot bool + reservePorts bool } // syncInfo is used to return data from monitor process to daemon @@ -75,7 +76,7 @@ type syncInfo struct { } // Make a new OCI runtime with provided options -func newOCIRuntime(name string, path string, conmonPath string, conmonEnv []string, cgroupManager string, tmpDir string, logSizeMax int64, noPivotRoot bool) (*OCIRuntime, error) { +func newOCIRuntime(name string, path string, conmonPath string, conmonEnv []string, cgroupManager string, tmpDir string, logSizeMax int64, noPivotRoot bool, reservePorts bool) (*OCIRuntime, error) { runtime := new(OCIRuntime) runtime.name = name runtime.path = path @@ -85,6 +86,7 @@ func newOCIRuntime(name string, path string, conmonPath string, conmonEnv []stri runtime.tmpDir = tmpDir runtime.logSizeMax = logSizeMax runtime.noPivot = noPivotRoot + runtime.reservePorts = reservePorts runtime.exitsDir = filepath.Join(runtime.tmpDir, "exits") runtime.socketsDir = filepath.Join(runtime.tmpDir, "socket") @@ -311,15 +313,17 @@ func (r *OCIRuntime) createOCIContainer(ctr *Container, cgroupParent string) (er cmd.Env = append(cmd.Env, fmt.Sprintf("_OCI_STARTPIPE=%d", 4)) cmd.Env = append(cmd.Env, fmt.Sprintf("XDG_RUNTIME_DIR=%s", runtimeDir)) - ports, err := bindPorts(ctr.config.PortMappings) - if err != nil { - return err - } + if r.reservePorts { + ports, err := bindPorts(ctr.config.PortMappings) + if err != nil { + return err + } - // Leak the port we bound in the conmon process. These fd's won't be used - // by the container and conmon will keep the ports busy so that another - // process cannot use them. - cmd.ExtraFiles = append(cmd.ExtraFiles, ports...) + // Leak the port we bound in the conmon process. These fd's won't be used + // by the container and conmon will keep the ports busy so that another + // process cannot use them. + cmd.ExtraFiles = append(cmd.ExtraFiles, ports...) + } if rootless.IsRootless() { ctr.rootlessSlirpSyncR, ctr.rootlessSlirpSyncW, err = os.Pipe() diff --git a/libpod/runtime.go b/libpod/runtime.go index 63b8c971e..736169932 100644 --- a/libpod/runtime.go +++ b/libpod/runtime.go @@ -164,6 +164,14 @@ type RuntimeConfig struct { InfraImage string `toml:"infra_image"` // InfraCommand is the command run to start up a pod infra container InfraCommand string `toml:"infra_command"` + // EnablePortReservation determines whether libpod will reserve ports on + // the host when they are forwarded to containers. + // When enabled, when ports are forwarded to containers, they are + // held open by conmon as long as the container is running, ensuring + // that they cannot be reused by other programs on the host. + // However, this can cause significant memory usage if a container has + // many ports forwarded to it. Disabling this can save memory. + EnablePortReservation bool `toml:"enable_port_reservation"` } var ( @@ -190,16 +198,17 @@ var ( ConmonEnvVars: []string{ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", }, - CgroupManager: SystemdCgroupsManager, - HooksDir: hooks.DefaultDir, - StaticDir: filepath.Join(storage.DefaultStoreOptions.GraphRoot, "libpod"), - TmpDir: "", - MaxLogSize: -1, - NoPivotRoot: false, - CNIConfigDir: "/etc/cni/net.d/", - CNIPluginDir: []string{"/usr/libexec/cni", "/usr/lib/cni", "/opt/cni/bin"}, - InfraCommand: DefaultInfraCommand, - InfraImage: DefaultInfraImage, + CgroupManager: SystemdCgroupsManager, + HooksDir: hooks.DefaultDir, + StaticDir: filepath.Join(storage.DefaultStoreOptions.GraphRoot, "libpod"), + TmpDir: "", + MaxLogSize: -1, + NoPivotRoot: false, + CNIConfigDir: "/etc/cni/net.d/", + CNIPluginDir: []string{"/usr/libexec/cni", "/usr/lib/cni", "/opt/cni/bin"}, + InfraCommand: DefaultInfraCommand, + InfraImage: DefaultInfraImage, + EnablePortReservation: true, } ) @@ -467,7 +476,8 @@ func makeRuntime(runtime *Runtime) (err error) { ociRuntime, err := newOCIRuntime("runc", runtime.ociRuntimePath, runtime.conmonPath, runtime.config.ConmonEnvVars, runtime.config.CgroupManager, runtime.config.TmpDir, - runtime.config.MaxLogSize, runtime.config.NoPivotRoot) + runtime.config.MaxLogSize, runtime.config.NoPivotRoot, + runtime.config.EnablePortReservation) if err != nil { return err } |