[#196] Support soft memory limit setting

Signed-off-by: Roman Loginov <r.loginov@yadro.com>

cmd/s3-gw/app.go

@@ -7,6 +7,7 @@ import (
 	"net/http"
 	"os"
 	"os/signal"
+	"runtime/debug"
 	"sync"
 	"sync/atomic"
 	"syscall"
@@ -119,6 +120,7 @@ func newApp(ctx context.Context, log *Logger, v *viper.Viper) *App {
 }
 
 func (a *App) init(ctx context.Context) {
+	a.setRuntimeParameters()
 	a.initAPI(ctx)
 	a.initMetrics()
 	a.initServers(ctx)
@@ -507,6 +509,8 @@ func (a *App) configReload(ctx context.Context) {
 		a.log.Warn(logs.FailedToReloadServerParameters, zap.Error(err))
 	}
 
+	a.setRuntimeParameters()
+
 	a.stopServices()
 	a.startServices()
 
@@ -679,3 +683,19 @@ func (a *App) initHandler() {
 		a.log.Fatal(logs.CouldNotInitializeAPIHandler, zap.Error(err))
 	}
 }
+
+func (a *App) setRuntimeParameters() {
+	if len(os.Getenv("GOMEMLIMIT")) != 0 {
+		// default limit < yaml limit < app env limit < GOMEMLIMIT
+		a.log.Warn(logs.RuntimeSoftMemoryDefinedWithGOMEMLIMIT)
+		return
+	}
+
+	softMemoryLimit := fetchSoftMemoryLimit(a.cfg)
+	previous := debug.SetMemoryLimit(softMemoryLimit)
+	if softMemoryLimit != previous {
+		a.log.Info(logs.RuntimeSoftMemoryLimitUpdated,
+			zap.Int64("new_value", softMemoryLimit),
+			zap.Int64("old_value", previous))
+	}
+}

cmd/s3-gw/app_settings.go

@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"math"
 	"os"
 	"path"
 	"runtime"
@@ -37,6 +38,8 @@ const (
 
 	defaultMaxClientsCount    = 100
 	defaultMaxClientsDeadline = time.Second * 30
+
+	defaultSoftMemoryLimit = math.MaxInt64
 )
 
 var defaultCopiesNumbers = []uint32{0}
@@ -154,6 +157,9 @@ const ( // Settings.
 	cfgResolveBucketAllow = "resolve_bucket.allow"
 	cfgResolveBucketDeny  = "resolve_bucket.deny"
 
+	// Runtime.
+	cfgSoftMemoryLimit = "runtime.soft_memory_limit"
+
 	// envPrefix is an environment variables prefix used for configuration.
 	envPrefix = "S3_GW"
 )
@@ -230,6 +236,15 @@ func fetchMaxClientsDeadline(cfg *viper.Viper) time.Duration {
 	return maxClientsDeadline
 }
 
+func fetchSoftMemoryLimit(cfg *viper.Viper) int64 {
+	softMemoryLimit := cfg.GetSizeInBytes(cfgSoftMemoryLimit)
+	if softMemoryLimit <= 0 {
+		softMemoryLimit = defaultSoftMemoryLimit
+	}
+
+	return int64(softMemoryLimit)
+}
+
 func fetchDefaultPolicy(l *zap.Logger, cfg *viper.Viper) netmap.PlacementPolicy {
 	var policy netmap.PlacementPolicy
 

config/config.env

@@ -146,3 +146,5 @@ S3_GW_BYPASS_CONTENT_ENCODING_CHECK_IN_CHUNKS=false
 S3_GW_TRACING_ENABLED=false
 S3_GW_TRACING_ENDPOINT="localhost:4318"
 S3_GW_TRACING_EXPORTER="otlp_grpc"
+
+S3_GW_RUNTIME_SOFT_MEMORY_LIMIT=1073741824

config/config.yaml

@@ -171,3 +171,6 @@ kludge:
   complete_multipart_keepalive: 10s
   # Use this flag to be able to use chunked upload approach without having `aws-chunked` value in `Content-Encoding` header.
   bypass_content_encoding_check_in_chunks: false
+
+runtime:
+  soft_memory_limit: 1gb

docs/configuration.md

@@ -185,6 +185,7 @@ There are some custom types used for brevity:
 | `frostfs`          | [Parameters of requests to FrostFS](#frostfs-section)          |
 | `resolve_bucket`   | [Bucket name resolving configuration](#resolve_bucket-section) |
 | `kludge`           | [Different kludge configuration](#kludge-section)              |
+| `runtime`          | [Runtime configuration](#runtime-section)                      |
 
 ### General section
 
@@ -547,3 +548,15 @@ kludge:
 | `use_default_xmlns_for_complete_multipart` | `bool`     | yes           | false         | Enable using default xml namespace `http://s3.amazonaws.com/doc/2006-03-01/` when parse `CompleteMultipartUpload` xml body.                                                                      |
 | `complete_multipart_keepalive`             | `duration` | no            | 10s           | Set timeout between whitespace transmissions during CompleteMultipartUpload processing.                                                                                                          |
 | `bypass_content_encoding_check_in_chunks`  | `bool`     | yes           | false         | Use this flag to be able to use [chunked upload approach](https://docs.aws.amazon.com/AmazonS3/latest/API/sigv4-streaming.html) without having `aws-chunked` value in `Content-Encoding` header. |
+
+# `runtime` section
+Contains runtime parameters.
+
+```yaml
+runtime:
+  soft_memory_limit: 1gb
+```
+
+| Parameter           | Type   | SIGHUP reload | Default value | Description                                                                                                                                                                  |
+|---------------------|--------|---------------|---------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `soft_memory_limit` | `size` | yes           | maxint64      | Soft memory limit for the runtime. Zero or no value stands for no limit. If `GOMEMLIMIT` environment variable is set, the value from the configuration file will be ignored. |

internal/logs/logs.go

@@ -112,4 +112,6 @@ const (
 	ListenAndServe                                       = "listen and serve"                                                                                  // Fatal in ../../cmd/s3-gw/app.go
 	NoHealthyServers                                     = "no healthy servers"                                                                                // Fatal in ../../cmd/s3-gw/app.go
 	CouldNotInitializeAPIHandler                         = "could not initialize API handler"                                                                  // Fatal in ../../cmd/s3-gw/app.go
+	RuntimeSoftMemoryDefinedWithGOMEMLIMIT               = "soft runtime memory defined with GOMEMLIMIT environment variable, config value skipped"            // Warn in ../../cmd/s3-gw/app.go
+	RuntimeSoftMemoryLimitUpdated                        = "soft runtime memory limit value updated"                                                           // Info in ../../cmd/s3-gw/app.go
 )