validate canons without yatest_common

1 files changed, 159 insertions, 0 deletions

diff --git a/library/go/maxprocs/maxprocs.go b/library/go/maxprocs/maxprocs.go
new file mode 100644
index 00000000000..b5996ec6bce
--- /dev/null
+++ b/library/go/maxprocs/maxprocs.go
@@ -0,0 +1,159 @@
+package maxprocs
+
+import (
+	"context"
+	"os"
+	"runtime"
+	"strings"
+
+	"a.yandex-team.ru/library/go/yandex/deploy/podagent"
+	"a.yandex-team.ru/library/go/yandex/yplite"
+)
+
+const (
+	SafeProc = 4
+	MinProc  = 2
+	MaxProc  = 8
+
+	GoMaxProcEnvName      = "GOMAXPROCS"
+	QloudCPUEnvName       = "QLOUD_CPU_GUARANTEE"
+	InstancectlCPUEnvName = "CPU_GUARANTEE"
+	DeloyBoxIDName        = podagent.EnvBoxIDKey
+)
+
+// Adjust adjust the maximum number of CPUs that can be executing.
+// Takes a minimum between n and CPU counts and returns the previous setting
+func Adjust(n int) int {
+	if n < MinProc {
+		n = MinProc
+	}
+
+	nCPU := runtime.NumCPU()
+	if n < nCPU {
+		return runtime.GOMAXPROCS(n)
+	}
+
+	return runtime.GOMAXPROCS(nCPU)
+}
+
+// AdjustAuto automatically adjust the maximum number of CPUs that can be executing to safe value
+// and returns the previous setting
+func AdjustAuto() int {
+	if val, ok := getEnv(GoMaxProcEnvName); ok {
+		return applyIntStringLimit(val)
+	}
+
+	if isCgroupsExists() {
+		return AdjustCgroup()
+	}
+
+	if val, ok := getEnv(InstancectlCPUEnvName); ok {
+		return applyFloatStringLimit(strings.TrimRight(val, "c"))
+	}
+
+	if val, ok := getEnv(QloudCPUEnvName); ok {
+		return applyFloatStringLimit(val)
+	}
+
+	if boxID, ok := os.LookupEnv(DeloyBoxIDName); ok {
+		return adjustYPBox(boxID)
+	}
+
+	if yplite.IsAPIAvailable() {
+		return AdjustYPLite()
+	}
+
+	return Adjust(SafeProc)
+}
+
+// AdjustQloud automatically adjust the maximum number of CPUs in case of Qloud env
+// and returns the previous setting
+func AdjustQloud() int {
+	if val, ok := getEnv(GoMaxProcEnvName); ok {
+		return applyIntStringLimit(val)
+	}
+
+	if val, ok := getEnv(QloudCPUEnvName); ok {
+		return applyFloatStringLimit(val)
+	}
+
+	return Adjust(MaxProc)
+}
+
+// AdjustYP automatically adjust the maximum number of CPUs in case of YP/Y.Deploy/YP.Hard env
+// and returns the previous setting
+func AdjustYP() int {
+	if val, ok := getEnv(GoMaxProcEnvName); ok {
+		return applyIntStringLimit(val)
+	}
+
+	if isCgroupsExists() {
+		return AdjustCgroup()
+	}
+
+	return adjustYPBox(os.Getenv(DeloyBoxIDName))
+}
+
+func adjustYPBox(boxID string) int {
+	resources, err := podagent.NewClient().PodAttributes(context.Background())
+	if err != nil {
+		return Adjust(SafeProc)
+	}
+
+	var cpuGuarantee float64
+	if boxResources, ok := resources.BoxesRequirements[boxID]; ok {
+		cpuGuarantee = boxResources.CPU.Guarantee / 1000
+	}
+
+	if cpuGuarantee <= 0 {
+		// if we don't have guarantees for current box, let's use pod guarantees
+		cpuGuarantee = resources.PodRequirements.CPU.Guarantee / 1000
+	}
+
+	return applyFloatLimit(cpuGuarantee)
+}
+
+// AdjustYPLite automatically adjust the maximum number of CPUs in case of YP.Lite env
+// and returns the previous setting
+func AdjustYPLite() int {
+	if val, ok := getEnv(GoMaxProcEnvName); ok {
+		return applyIntStringLimit(val)
+	}
+
+	podAttributes, err := yplite.FetchPodAttributes()
+	if err != nil {
+		return Adjust(SafeProc)
+	}
+
+	return applyFloatLimit(float64(podAttributes.ResourceRequirements.CPU.Guarantee / 1000))
+}
+
+// AdjustInstancectl automatically adjust the maximum number of CPUs
+// and returns the previous setting
+// WARNING: supported only instancectl v1.177+ (https://wiki.yandex-team.ru/runtime-cloud/nanny/instancectl-change-log/#1.177)
+func AdjustInstancectl() int {
+	if val, ok := getEnv(GoMaxProcEnvName); ok {
+		return applyIntStringLimit(val)
+	}
+
+	if val, ok := getEnv(InstancectlCPUEnvName); ok {
+		return applyFloatStringLimit(strings.TrimRight(val, "c"))
+	}
+
+	return Adjust(MaxProc)
+}
+
+// AdjustCgroup automatically adjust the maximum number of CPUs based on the CFS quota
+// and returns the previous setting.
+func AdjustCgroup() int {
+	if val, ok := getEnv(GoMaxProcEnvName); ok {
+		return applyIntStringLimit(val)
+	}
+
+	quota, err := getCFSQuota()
+	if err != nil {
+		return Adjust(SafeProc)
+	}
+
+	return applyFloatLimit(quota)
+}