Files
podman/pkg/specgen/generate/validate.go
OpenShift Merge Robot 2aaa036f56 Merge pull request #8197 from giuseppe/check-cgroupv2-swap-enabled
specgen, cgroup2: check whether memory swap is enabled
2020-10-31 11:40:07 +01:00

207 lines
8.5 KiB
Go

package generate
import (
"os"
"path/filepath"
"github.com/containers/common/pkg/sysinfo"
"github.com/containers/podman/v2/pkg/cgroups"
"github.com/containers/podman/v2/pkg/specgen"
"github.com/containers/podman/v2/utils"
"github.com/pkg/errors"
)
// Verify resource limits are sanely set when running on cgroup v1.
func verifyContainerResourcesCgroupV1(s *specgen.SpecGenerator) ([]string, error) {
warnings := []string{}
sysInfo := sysinfo.New(true)
if s.ResourceLimits == nil {
return warnings, nil
}
if s.ResourceLimits.Unified != nil {
return nil, errors.New("Cannot use --cgroup-conf without cgroup v2")
}
// Memory checks
if s.ResourceLimits.Memory != nil {
memory := s.ResourceLimits.Memory
if memory.Limit != nil && !sysInfo.MemoryLimit {
warnings = append(warnings, "Your kernel does not support memory limit capabilities or the cgroup is not mounted. Limitation discarded.")
memory.Limit = nil
memory.Swap = nil
}
if memory.Limit != nil && memory.Swap != nil && !sysInfo.SwapLimit {
warnings = append(warnings, "Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.")
memory.Swap = nil
}
if memory.Limit != nil && memory.Swap != nil && *memory.Swap < *memory.Limit {
return warnings, errors.New("minimum memoryswap limit should be larger than memory limit, see usage")
}
if memory.Limit == nil && memory.Swap != nil {
return warnings, errors.New("you should always set a memory limit when using a memoryswap limit, see usage")
}
if memory.Swappiness != nil {
if !sysInfo.MemorySwappiness {
warnings = append(warnings, "Your kernel does not support memory swappiness capabilities, or the cgroup is not mounted. Memory swappiness discarded.")
memory.Swappiness = nil
} else {
if *memory.Swappiness < 0 || *memory.Swappiness > 100 {
return warnings, errors.Errorf("invalid value: %v, valid memory swappiness range is 0-100", *memory.Swappiness)
}
}
}
if memory.Reservation != nil && !sysInfo.MemoryReservation {
warnings = append(warnings, "Your kernel does not support memory soft limit capabilities or the cgroup is not mounted. Limitation discarded.")
memory.Reservation = nil
}
if memory.Limit != nil && memory.Reservation != nil && *memory.Limit < *memory.Reservation {
return warnings, errors.New("minimum memory limit cannot be less than memory reservation limit, see usage")
}
if memory.Kernel != nil && !sysInfo.KernelMemory {
warnings = append(warnings, "Your kernel does not support kernel memory limit capabilities or the cgroup is not mounted. Limitation discarded.")
memory.Kernel = nil
}
if memory.DisableOOMKiller != nil && *memory.DisableOOMKiller && !sysInfo.OomKillDisable {
warnings = append(warnings, "Your kernel does not support OomKillDisable. OomKillDisable discarded.")
memory.DisableOOMKiller = nil
}
}
// Pids checks
if s.ResourceLimits.Pids != nil {
pids := s.ResourceLimits.Pids
// TODO: Should this be 0, or checking that ResourceLimits.Pids
// is set at all?
if pids.Limit > 0 && !sysInfo.PidsLimit {
warnings = append(warnings, "Your kernel does not support pids limit capabilities or the cgroup is not mounted. PIDs limit discarded.")
s.ResourceLimits.Pids = nil
}
}
// CPU Checks
if s.ResourceLimits.CPU != nil {
cpu := s.ResourceLimits.CPU
if cpu.Shares != nil && !sysInfo.CPUShares {
warnings = append(warnings, "Your kernel does not support CPU shares or the cgroup is not mounted. Shares discarded.")
cpu.Shares = nil
}
if cpu.Period != nil && !sysInfo.CPUCfsPeriod {
warnings = append(warnings, "Your kernel does not support CPU cfs period or the cgroup is not mounted. Period discarded.")
cpu.Period = nil
}
if cpu.Period != nil && (*cpu.Period < 1000 || *cpu.Period > 1000000) {
return warnings, errors.New("CPU cfs period cannot be less than 1ms (i.e. 1000) or larger than 1s (i.e. 1000000)")
}
if cpu.Quota != nil && !sysInfo.CPUCfsQuota {
warnings = append(warnings, "Your kernel does not support CPU cfs quota or the cgroup is not mounted. Quota discarded.")
cpu.Quota = nil
}
if cpu.Quota != nil && *cpu.Quota < 1000 {
return warnings, errors.New("CPU cfs quota cannot be less than 1ms (i.e. 1000)")
}
if (cpu.Cpus != "" || cpu.Mems != "") && !sysInfo.Cpuset {
warnings = append(warnings, "Your kernel does not support cpuset or the cgroup is not mounted. CPUset discarded.")
cpu.Cpus = ""
cpu.Mems = ""
}
cpusAvailable, err := sysInfo.IsCpusetCpusAvailable(cpu.Cpus)
if err != nil {
return warnings, errors.Errorf("invalid value %s for cpuset cpus", cpu.Cpus)
}
if !cpusAvailable {
return warnings, errors.Errorf("requested CPUs are not available - requested %s, available: %s", cpu.Cpus, sysInfo.Cpus)
}
memsAvailable, err := sysInfo.IsCpusetMemsAvailable(cpu.Mems)
if err != nil {
return warnings, errors.Errorf("invalid value %s for cpuset mems", cpu.Mems)
}
if !memsAvailable {
return warnings, errors.Errorf("requested memory nodes are not available - requested %s, available: %s", cpu.Mems, sysInfo.Mems)
}
}
// Blkio checks
if s.ResourceLimits.BlockIO != nil {
blkio := s.ResourceLimits.BlockIO
if blkio.Weight != nil && !sysInfo.BlkioWeight {
warnings = append(warnings, "Your kernel does not support Block I/O weight or the cgroup is not mounted. Weight discarded.")
blkio.Weight = nil
}
if blkio.Weight != nil && (*blkio.Weight > 1000 || *blkio.Weight < 10) {
return warnings, errors.New("range of blkio weight is from 10 to 1000")
}
if len(blkio.WeightDevice) > 0 && !sysInfo.BlkioWeightDevice {
warnings = append(warnings, "Your kernel does not support Block I/O weight_device or the cgroup is not mounted. Weight-device discarded.")
blkio.WeightDevice = nil
}
if len(blkio.ThrottleReadBpsDevice) > 0 && !sysInfo.BlkioReadBpsDevice {
warnings = append(warnings, "Your kernel does not support BPS Block I/O read limit or the cgroup is not mounted. Block I/O BPS read limit discarded")
blkio.ThrottleReadBpsDevice = nil
}
if len(blkio.ThrottleWriteBpsDevice) > 0 && !sysInfo.BlkioWriteBpsDevice {
warnings = append(warnings, "Your kernel does not support BPS Block I/O write limit or the cgroup is not mounted. Block I/O BPS write limit discarded.")
blkio.ThrottleWriteBpsDevice = nil
}
if len(blkio.ThrottleReadIOPSDevice) > 0 && !sysInfo.BlkioReadIOpsDevice {
warnings = append(warnings, "Your kernel does not support IOPS Block read limit or the cgroup is not mounted. Block I/O IOPS read limit discarded.")
blkio.ThrottleReadIOPSDevice = nil
}
if len(blkio.ThrottleWriteIOPSDevice) > 0 && !sysInfo.BlkioWriteIOpsDevice {
warnings = append(warnings, "Your kernel does not support IOPS Block I/O write limit or the cgroup is not mounted. Block I/O IOPS write limit discarded.")
blkio.ThrottleWriteIOPSDevice = nil
}
}
return warnings, nil
}
// Verify resource limits are sanely set when running on cgroup v2.
func verifyContainerResourcesCgroupV2(s *specgen.SpecGenerator) ([]string, error) {
warnings := []string{}
if s.ResourceLimits == nil {
return warnings, nil
}
if s.ResourceLimits.Memory != nil && s.ResourceLimits.Memory.Swap != nil {
own, err := utils.GetOwnCgroup()
if err != nil {
return warnings, err
}
memoryMax := filepath.Join("/sys/fs/cgroup", own, "memory.max")
memorySwapMax := filepath.Join("/sys/fs/cgroup", own, "memory.swap.max")
_, errMemoryMax := os.Stat(memoryMax)
_, errMemorySwapMax := os.Stat(memorySwapMax)
// Differently than cgroup v1, the memory.*max files are not present in the
// root directory, so we cannot query directly that, so as best effort use
// the current cgroup.
// Check whether memory.max exists in the current cgroup and memory.swap.max
// does not. In this case we can be sure memory swap is not enabled.
// If both files don't exist, the memory controller might not be enabled
// for the current cgroup.
if errMemoryMax == nil && errMemorySwapMax != nil {
warnings = append(warnings, "Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.")
s.ResourceLimits.Memory.Swap = nil
}
}
return warnings, nil
}
// Verify resource limits are sanely set, removing any limits that are not
// possible with the current cgroups config.
func verifyContainerResources(s *specgen.SpecGenerator) ([]string, error) {
cgroup2, err := cgroups.IsCgroup2UnifiedMode()
if err != nil {
return []string{}, err
}
if cgroup2 {
return verifyContainerResourcesCgroupV2(s)
}
return verifyContainerResourcesCgroupV1(s)
}