minio/internal/ioutil/read_file.go
Harshavardhana 5a9f133491
speed up startup sequence for all operations (#14148)
This speed-up is intended for faster startup times
for almost all MinIO operations. Changes here are

- Drives are not re-read for 'format.json' on a regular
  basis once read during init is remembered and refreshed
  at 5 second intervals.

- Do not do O_DIRECT tests on drives with existing 'format.json'
  only fresh setups need this check.

- Parallelize initializing erasureSets for multiple sets.

- Avoid re-reading format.json when migrating 'format.json'
  from really old V1->V2->V3

- Keep a copy of local drives for any given server in memory
  for a quick lookup.
2022-01-24 11:28:45 -08:00

79 lines
2.2 KiB
Go

// Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package ioutil
import (
"io"
"io/fs"
"os"
"github.com/minio/minio/internal/disk"
)
// ReadFileWithFileInfo reads the named file and returns the contents.
// A successful call returns err == nil, not err == EOF.
// Because ReadFile reads the whole file, it does not treat an EOF from Read
// as an error to be reported, additionall returns os.FileInfo
func ReadFileWithFileInfo(name string) ([]byte, fs.FileInfo, error) {
f, err := os.Open(name)
if err != nil {
return nil, nil, err
}
defer f.Close()
st, err := f.Stat()
if err != nil {
return nil, nil, err
}
dst := make([]byte, st.Size())
_, err = io.ReadFull(f, dst)
return dst, st, err
}
// ReadFile reads the named file and returns the contents.
// A successful call returns err == nil, not err == EOF.
// Because ReadFile reads the whole file, it does not treat an EOF from Read
// as an error to be reported.
//
// passes NOATIME flag for reads on Unix systems to avoid atime updates.
func ReadFile(name string) ([]byte, error) {
f, err := disk.OpenFileDirectIO(name, readMode, 0o666)
if err != nil {
// fallback if there is an error to read
// 'name' with O_DIRECT
f, err = os.OpenFile(name, readMode, 0o666)
if err != nil {
return nil, err
}
}
r := &ODirectReader{
File: f,
SmallFile: true,
}
defer r.Close()
st, err := f.Stat()
if err != nil {
return io.ReadAll(r)
}
dst := make([]byte, st.Size())
_, err = io.ReadFull(r, dst)
return dst, err
}