cmd/utils/fdlimit_unix.go


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50

// Copyright 2016 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.

// +build linux darwin netbsd openbsd solaris

package utils

import "syscall"

// raiseFdLimit tries to maximize the file descriptor allowance of this process
// to the maximum hard-limit allowed by the OS.
func raiseFdLimit(max uint64) error {
    // Get the current limit
    var limit syscall.Rlimit
    if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
        return err
    }
    // Try to update the limit to the max allowance
    limit.Cur = limit.Max
    if limit.Cur > max {
        limit.Cur = max
    }
    if err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
        return err
    }
    return nil
}

// getFdLimit retrieves the number of file descriptors allowed to be opened by this
// process.
func getFdLimit() (int, error) {
    var limit syscall.Rlimit
    if err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &limit); err != nil {
        return 0, err
    }
    return int(limit.Cur), nil
}