github.com/MetalBlockchain/metalgo@v1.11.9/utils/ulimit/ulimit_darwin.go (about)

     1  // Copyright (C) 2019-2024, Ava Labs, Inc. All rights reserved.
     2  // See the file LICENSE for licensing terms.
     3  
     4  //go:build darwin
     5  // +build darwin
     6  
     7  package ulimit
     8  
     9  import (
    10  	"fmt"
    11  	"syscall"
    12  
    13  	"go.uber.org/zap"
    14  
    15  	"github.com/MetalBlockchain/metalgo/utils/logging"
    16  )
    17  
    18  const DefaultFDLimit = 10 * 1024
    19  
    20  // Set attempts to bump the Rlimit which has a soft (Cur) and a hard (Max) value.
    21  // The soft limit is what is used by the kernel to report EMFILE errors. The hard
    22  // limit is a secondary limit which the process can be bumped to without additional
    23  // privileges. Bumping the Max limit further would require superuser privileges.
    24  // If the value is below the recommendation warn on start.
    25  // see: http://0pointer.net/blog/file-descriptor-limits.html
    26  func Set(max uint64, log logging.Logger) error {
    27  	var rLimit syscall.Rlimit
    28  	err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rLimit)
    29  	if err != nil {
    30  		return fmt.Errorf("error getting rlimit: %w", err)
    31  	}
    32  
    33  	// Darwin max number of FDs to allocatable for darwin systems.
    34  	// The max file limit is 10240, even though the max returned by
    35  	// Getrlimit is 1<<63-1. This is OPEN_MAX in sys/syslimits.h.
    36  	// See https://github.com/golang/go/issues/30401
    37  	if max > DefaultFDLimit {
    38  		return fmt.Errorf("error fd-limit: (%d) greater than max: (%d)", max, DefaultFDLimit)
    39  	}
    40  
    41  	rLimit.Cur = max
    42  
    43  	// set new limit
    44  	if err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rLimit); err != nil {
    45  		return fmt.Errorf("error setting fd-limit: %w", err)
    46  	}
    47  
    48  	// verify limit
    49  	if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rLimit); err != nil {
    50  		return fmt.Errorf("error getting rlimit: %w", err)
    51  	}
    52  
    53  	if rLimit.Cur < DefaultFDLimit {
    54  		log.Warn("fd-limit is less than recommended and could result in reduced performance",
    55  			zap.Uint64("currentLimit", rLimit.Cur),
    56  			zap.Uint64("recommendedLimit", DefaultFDLimit),
    57  		)
    58  	}
    59  
    60  	return nil
    61  }