51 lines
1.9 KiB
Go
51 lines
1.9 KiB
Go
// Copyright 2018 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package fdlimit
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import "fmt"
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// hardlimit is the number of file descriptors allowed at max by the kernel.
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const hardlimit = 16384
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// Raise tries to maximize the file descriptor allowance of this process
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// to the maximum hard-limit allowed by the OS.
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func Raise(max uint64) (uint64, error) {
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// This method is NOP by design:
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// * Linux/Darwin counterparts need to manually increase per process limits
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// * On Windows Go uses the CreateFile API, which is limited to 16K files, non
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// changeable from within a running process
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// This way we can always "request" raising the limits, which will either have
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// or not have effect based on the platform we're running on.
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if max > hardlimit {
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return hardlimit, fmt.Errorf("file descriptor limit (%d) reached", hardlimit)
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}
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return max, nil
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}
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// Current retrieves the number of file descriptors allowed to be opened by this
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// process.
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func Current() (int, error) {
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// Please see Raise for the reason why we use hard coded 16K as the limit
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return hardlimit, nil
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}
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// Maximum retrieves the maximum number of file descriptors this process is
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// allowed to request for itself.
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func Maximum() (int, error) {
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return Current()
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}
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