Add util to raise file descriptor limits

main/params.go

@@ -24,6 +24,7 @@ import (
 	"github.com/ava-labs/gecko/staking"
 	"github.com/ava-labs/gecko/utils"
 	"github.com/ava-labs/gecko/utils/constants"
+	"github.com/ava-labs/gecko/utils/fdlimit"
 	"github.com/ava-labs/gecko/utils/hashing"
 	"github.com/ava-labs/gecko/utils/logging"
 	"github.com/ava-labs/gecko/utils/sampler"
@@ -239,6 +240,10 @@ func init() {
 	ipcsChainIDs := fs.String("ipcs-chain-ids", "", "Comma separated list of chain ids to add to the IPC engine. Example: 11111111111111111111111111111111LpoYY,4R5p2RXDGLqaifZE4hHWH9owe34pfoBULn1DrQTWivjg8o4aH")
 	fs.StringVar(&Config.IPCPath, "ipcs-path", ipcs.DefaultBaseURL, "The directory (Unix) or named pipe name prefix (Windows) for IPC sockets")
 
+	// File Descriptors
+	var fdLimit uint64
+	fs.Uint64Var(&fdLimit, "fd-limit", fdlimit.DefaultFdLimit, "Attempts to raise the process file descriptor limit to at least this value.")
+
 	ferr := fs.Parse(os.Args[1:])
 
 	if *version { // If --version used, print version and exit
@@ -444,4 +449,10 @@ func init() {
 	if *ipcsChainIDs != "" {
 		Config.IPCDefaultChainIDs = strings.Split(*ipcsChainIDs, ",")
 	}
+
+	// File Descriptors
+	if err := fdlimit.RaiseLimit(fdLimit); err != nil {
+		errs.Add(err)
+		return
+	}
 }

utils/fdlimit/fdlimit.go

@@ -0,0 +1,61 @@
+// (c) 2019-2020, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+// +build !windows
+
+package fdlimit
+
+import (
+	"fmt"
+	"syscall"
+)
+
+const (
+	// DefaultFdLimit is the default value to raise the file
+	// descriptor limit to on startup.
+	DefaultFdLimit uint64 = 4096
+)
+
+// Based off of Quorum implementation:
+// https://github.com/ConsenSys/quorum/tree/c215989c10f191924e6b5b668ba4ed8ed425ded1/common/fdlimit
+
+// GetLimit returns the current and max file descriptor limit
+func GetLimit() (uint64, uint64, error) {
+	var limit syscall.Rlimit
+	err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &limit)
+	return limit.Cur, limit.Max, err
+}
+
+// RaiseLimit attempts to raise the file descriptor limit to at least [fdLimit]
+func RaiseLimit(fdLimit uint64) error {
+	// Get the current and maximum file descriptor limit
+	var limit syscall.Rlimit
+	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
+		return err
+	}
+
+	// Check if it is necessary or possible to raise the file descriptor limit
+	if limit.Cur >= fdLimit {
+		return nil
+	}
+	if limit.Max < fdLimit {
+		return fmt.Errorf("Cannot raise fd limit to %d because it is above system maximum of %d", fdLimit, limit.Max)
+	}
+
+	// Attempt to increase the file descriptor limit to [fdLimit]
+	limit.Cur = fdLimit
+	if err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
+		return err
+	}
+
+	// Get the limit one last time to ensure that the OS made
+	// the requested change
+	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
+		return err
+	}
+	if limit.Cur < fdLimit {
+		return fmt.Errorf("Raising the fd limit failed to take effect")
+	}
+
+	return nil
+}

utils/fdlimit/fdlimit_test.go

@@ -0,0 +1,28 @@
+// (c) 2019-2020, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package fdlimit
+
+import "testing"
+
+// Based off of Quorum implementation:
+// https://github.com/ConsenSys/quorum/tree/c215989c10f191924e6b5b668ba4ed8ed425ded1/common/fdlimit
+
+func TestFileDescriptorLimits(t *testing.T) {
+	_, _, err := GetLimit()
+	if err != nil {
+		t.Fatalf("Failed to get file descriptor limits: %s", err)
+	}
+
+	if err := RaiseLimit(DefaultFdLimit); err != nil {
+		t.Fatalf("Failed to raise file descriptor limit: %s", err)
+	}
+
+	cur, _, err := GetLimit()
+	if err != nil {
+		t.Fatalf("Failed to get file descriptor limits after attempting to raise the limit: %s", err)
+	}
+	if cur < DefaultFdLimit {
+		t.Fatalf("Failed to raise the file descriptor limit. Target: %d. Current Value: %d.", DefaultFdLimit, cur)
+	}
+}

utils/fdlimit/fdlimit_windows.go

@@ -0,0 +1,37 @@
+// (c) 2019-2020, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+// This tag is applied for consistency with fdlimit.go, but
+// is redundant because this file also uses *_windows.go suffix
+// +build windows
+
+package fdlimit
+
+import (
+	"fmt"
+)
+
+const (
+	// DefaultFdLimit is the default value to raise the file
+	// descriptor limit to on startup.
+	DefaultFdLimit uint64 = 4096
+	// Cannot adjust the fd limit set by the Windows OS
+	// so these operations are NOPs
+	windowsHardLimit uint64 = 16384
+)
+
+// Based off of Quorum implementation:
+// https://github.com/ConsenSys/quorum/tree/c215989c10f191924e6b5b668ba4ed8ed425ded1/common/fdlimit
+
+// GetLimit returns the current and max file descriptor limit
+func GetLimit() (uint64, uint64, error) {
+	return windowsHardLimit, windowsHardLimit, nil
+}
+
+// RaiseLimit attempts to raise the file descriptor limit to at least [fdLimit]
+func RaiseLimit(fdLimit uint64) error {
+	if fdLimit > windowsHardLimit {
+		return fmt.Errorf("Cannot raise the file descriptor limit above %d to %d on Windows OS", windowsHardLimit, fdLimit)
+	}
+	return nil
+}