Add details for setting memory limit automatically. (#655)

* Add details for setting memory limit automatically.

* fix typo

* Update docs/sources/reference/cli/run.md

Co-authored-by: Mischa Thompson <mischabear@gmail.com>

* Update internal/alloycli/cmd_run.go

Co-authored-by: Mischa Thompson <mischabear@gmail.com>

* add logging

* Mark as public preview.

* Mark as public preview.

* pr feedback

* use default logger

---------

Co-authored-by: Mischa Thompson <mischabear@gmail.com>

CHANGELOG.md

@@ -10,6 +10,10 @@ internal API changes are not present.
 Main (unreleased)
 -----------------
 
+### Features
+
+- (_Public preview_) Add support for setting GOMEMLIMIT based on cgroup setting. (@mattdurham)
+
 ### Enhancements
 
 - Update `prometheus.exporter.kafka` with the following functionalities (@wildum):

docs/sources/reference/cli/run.md

@@ -164,6 +164,7 @@ original configuration.
 Include `--config.extra-args` to pass additional command line flags from the original format to the converter.
 Refer to [alloy convert][] for more details on how `extra-args` work.
 
+
 [alloy convert]: ../convert/
 [clustering]:  ../../../concepts/clustering/
 [go-discover]: https://github.com/hashicorp/go-discover

go.mod

@@ -258,6 +258,7 @@ require (
 )
 
 require (
+	github.com/KimMachineGun/automemlimit v0.6.0
 	github.com/Shopify/sarama v1.38.1
 	github.com/grafana/kafka_exporter v0.0.0-20240409084445-5e3488ad9f9a
 )
@@ -355,6 +356,7 @@ require (
 	github.com/cloudflare/golz4 v0.0.0-20150217214814-ef862a3cdc58 // indirect
 	github.com/cncf/xds/go v0.0.0-20231128003011-0fa0005c9caa // indirect
 	github.com/containerd/cgroups v1.1.0 // indirect
+	github.com/containerd/cgroups/v3 v3.0.2 // indirect
 	github.com/containerd/console v1.0.3 // indirect
 	github.com/containerd/containerd v1.7.11 // indirect
 	github.com/containerd/continuity v0.4.2 // indirect
@@ -579,6 +581,7 @@ require (
 	github.com/ovh/go-ovh v1.4.3 // indirect
 	github.com/packethost/packngo v0.1.1-0.20180711074735-b9cb5096f54c // indirect
 	github.com/patrickmn/go-cache v2.1.0+incompatible // indirect
+	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
 	github.com/pelletier/go-toml/v2 v2.1.0 // indirect
 	github.com/pierrec/lz4/v4 v4.1.21 // indirect
 	github.com/pjbgf/sha1cd v0.3.0 // indirect

go.sum

@@ -193,6 +193,8 @@ github.com/IBM/sarama v1.43.0/go.mod h1:zlE6HEbC/SMQ9mhEYaF7nNLYOUyrs0obySKCckWP
 github.com/Jeffail/gabs v1.1.0/go.mod h1:6xMvQMK4k33lb7GUUpaAPh6nKMmemQeg5d4gn7/bOXc=
 github.com/JohnCGriffin/overflow v0.0.0-20211019200055-46fa312c352c h1:RGWPOewvKIROun94nF7v2cua9qP+thov/7M50KEoeSU=
 github.com/JohnCGriffin/overflow v0.0.0-20211019200055-46fa312c352c/go.mod h1:X0CRv0ky0k6m906ixxpzmDRLvX58TFUKS2eePweuyxk=
+github.com/KimMachineGun/automemlimit v0.6.0 h1:p/BXkH+K40Hax+PuWWPQ478hPjsp9h1CPDhLlA3Z37E=
+github.com/KimMachineGun/automemlimit v0.6.0/go.mod h1:T7xYht7B8r6AG/AqFcUdc7fzd2bIdBKmepfP2S1svPY=
 github.com/Knetic/govaluate v3.0.1-0.20171022003610-9aa49832a739+incompatible/go.mod h1:r7JcOSlj0wfOMncg0iLm8Leh48TZaKVeNIfJntJ2wa0=
 github.com/Lusitaniae/apache_exporter v0.11.1-0.20220518131644-f9522724dab4 h1:UEm6tMvLH2t2honcWG0q+h0qr/60++9cuh/fy7hLyMc=
 github.com/Lusitaniae/apache_exporter v0.11.1-0.20220518131644-f9522724dab4/go.mod h1:IfUbHkoXypdKnVGHWQ3DLRRRZzIU/JIExQAd9xgxRfw=
@@ -474,6 +476,8 @@ github.com/cockroachdb/datadriven v0.0.0-20190809214429-80d97fb3cbaa/go.mod h1:z
 github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd/go.mod h1:sE/e/2PUdi/liOCUjSTXgM1o87ZssimdTWN964YiIeI=
 github.com/containerd/cgroups v1.1.0 h1:v8rEWFl6EoqHB+swVNjVoCJE8o3jX7e8nqBGPLaDFBM=
 github.com/containerd/cgroups v1.1.0/go.mod h1:6ppBcbh/NOOUU+dMKrykgaBnK9lCIBxHqJDGwsa1mIw=
+github.com/containerd/cgroups/v3 v3.0.2 h1:f5WFqIVSgo5IZmtTT3qVBo6TzI1ON6sycSBKkymb9L0=
+github.com/containerd/cgroups/v3 v3.0.2/go.mod h1:JUgITrzdFqp42uI2ryGA+ge0ap/nxzYgkGmIcetmErE=
 github.com/containerd/console v1.0.2/go.mod h1:ytZPjGgY2oeTkAONYafi2kSj0aYggsf8acV1PGKCbzQ=
 github.com/containerd/console v1.0.3 h1:lIr7SlA5PxZyMV30bDW0MGbiOPXwc63yRuCP0ARubLw=
 github.com/containerd/console v1.0.3/go.mod h1:7LqA/THxQ86k76b8c/EMSiaJ3h1eZkMkXar0TQ1gf3U=
@@ -1855,6 +1859,8 @@ github.com/pascaldekloe/goe v0.1.0/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144T
 github.com/patrickmn/go-cache v0.0.0-20180527043350-9f6ff22cfff8/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
+github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 h1:onHthvaw9LFnH4t2DcNVpwGmV9E1BkGknEliJkfwQj0=
+github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58/go.mod h1:DXv8WO4yhMYhSNPKjeNKa5WY9YCIEBRbNzFFPJbWO6Y=
 github.com/pborman/getopt v0.0.0-20180811024354-2b5b3bfb099b/go.mod h1:85jBQOZwpVEaDAr341tbn15RS4fCAsIst0qp7i8ex1o=
 github.com/pborman/uuid v1.2.0/go.mod h1:X/NO0urCmaxf9VXbdlT7C2Yzkj2IKimNn4k+gtPdI/k=
 github.com/pelletier/go-toml v1.7.0/go.mod h1:vwGMzjaWMwyfHwgIBhI2YUM4fB6nL6lVAvS1LBMMhTE=

internal/alloycli/cmd_run.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io/fs"
+	"log/slog"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -15,6 +16,7 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/KimMachineGun/automemlimit/memlimit"
 	"github.com/fatih/color"
 	"github.com/go-kit/log"
 	"github.com/grafana/alloy/internal/alloy"
@@ -192,6 +194,12 @@ func (fr *alloyRun) Run(configPath string) error {
 
 	level.Info(l).Log("boringcrypto enabled", boringcrypto.Enabled)
 
+	// Set the memory limit, this will honor GOMEMLIMIT if set
+	// If there is a cgroup will follow that
+	if fr.minStability.Permits(featuregate.StabilityPublicPreview) {
+		memlimit.SetGoMemLimitWithOpts(memlimit.WithLogger(slog.Default()))
+	}
+
 	// Enable the profiling.
 	setMutexBlockProfiling(l)
 

internal/featuregate/featuregate.go

@@ -97,3 +97,8 @@ func (s *Stability) Set(str string) error {
 func (s Stability) Type() string {
 	return "<stability_level>"
 }
+
+// Permits will check if the stability level is allowed. For instance experimental would allow public preview, experimental and ga. Whereas ga would only allow ga.
+func (s Stability) Permits(stability Stability) bool {
+	return s <= stability
+}

internal/featuregate/featuregate_test.go

@@ -63,3 +63,70 @@ func TestCheckAllowed(t *testing.T) {
 		})
 	}
 }
+
+func TestAllow(t *testing.T) {
+	type args struct {
+		current  Stability
+		required Stability
+		result   bool
+	}
+	tests := []struct {
+		name string
+		args args
+	}{
+		{
+			name: "Experimental to Experimental",
+			args: args{
+				current:  StabilityExperimental,
+				required: StabilityExperimental,
+				result:   true,
+			},
+		},
+		{
+			name: "Experimental to Public Preview",
+			args: args{
+				current:  StabilityExperimental,
+				required: StabilityPublicPreview,
+				result:   true,
+			},
+		},
+		{
+			name: "Experimental to GA",
+			args: args{
+				current:  StabilityExperimental,
+				required: StabilityPublicPreview,
+				result:   true,
+			},
+		},
+		{
+			name: "GA to GA",
+			args: args{
+				current:  StabilityGenerallyAvailable,
+				required: StabilityGenerallyAvailable,
+				result:   true,
+			},
+		},
+		{
+			name: "GA to Experimental",
+			args: args{
+				current:  StabilityGenerallyAvailable,
+				required: StabilityExperimental,
+				result:   false,
+			},
+		},
+		{
+			name: "GA to Public Preview",
+			args: args{
+				current:  StabilityGenerallyAvailable,
+				required: StabilityPublicPreview,
+				result:   false,
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := tt.args.current.Permits(tt.args.required)
+			require.True(t, result == tt.args.result)
+		})
+	}
+}