github.com/johnwhitton/go-ethereum@v1.8.23/common/fdlimit/fdlimit_windows.go (about) 1 // Copyright 2018 The go-ethereum Authors 2 // This file is part of the go-ethereum library. 3 // 4 // The go-ethereum library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-ethereum library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. 16 17 package fdlimit 18 19 import "fmt" 20 21 const hardlimit = 16384 22 23 // Raise tries to maximize the file descriptor allowance of this process 24 // to the maximum hard-limit allowed by the OS. 25 func Raise(max uint64) (uint64, error) { 26 // This method is NOP by design: 27 // * Linux/Darwin counterparts need to manually increase per process limits 28 // * On Windows Go uses the CreateFile API, which is limited to 16K files, non 29 // changeable from within a running process 30 // This way we can always "request" raising the limits, which will either have 31 // or not have effect based on the platform we're running on. 32 if max > hardlimit { 33 return hardlimit, fmt.Errorf("file descriptor limit (%d) reached", hardlimit) 34 } 35 return max, nil 36 } 37 38 // Current retrieves the number of file descriptors allowed to be opened by this 39 // process. 40 func Current() (int, error) { 41 // Please see Raise for the reason why we use hard coded 16K as the limit 42 return hardlimit, nil 43 } 44 45 // Maximum retrieves the maximum number of file descriptors this process is 46 // allowed to request for itself. 47 func Maximum() (int, error) { 48 return Current() 49 }