minio/cmd/storage-interface.go
Klaus Post b890bbfa63
Add local disk health checks (#14447)
The main goal of this PR is to solve the situation where disks stop 
responding to operations. This generally causes an FD build-up and 
eventually will crash the server.

This adds detection of hung disks, where calls on disk get stuck.

We add functionality to `xlStorageDiskIDCheck` where it keeps 
track of the number of concurrent requests on a given disk.

A total number of 100 operations are allowed. If this limit is reached 
we will block (but not reject) new requests, but we will monitor the 
state of the disk.

If no requests have been completed or updated within a 15-second 
window, we mark the disk as offline. Requests that are blocked will be 
unblocked and return an error as "faulty disk".

New requests will be rejected until the disk is marked OK again.

Once a disk has been marked faulty, a check will run every 5 seconds that 
will attempt to write and read back a file. As long as this fails the disk will 
remain faulty.

To prevent lots of long-running requests to mark the disk faulty we 
implement a callback feature that allows updating the status as parts 
of these operations are running.

We add a reader and writer wrapper that will update the status of each 
successful read/write operation. This should allow fine enough granularity 
that a slow, but still operational disk will not reach 15 seconds where 
50 operations have not progressed.

Note that errors themselves are not enough to mark a disk faulty. 
A nil (or io.EOF) error will mark a disk as "good".

* Make concurrent disk setting configurable via `_MINIO_DISK_MAX_CONCURRENT`.

* de-couple IsOnline() from disk health tracker

The purpose of IsOnline() is to ensure that we
reconnect the drive only when the "drive" was

- disconnected from network we need to validate
  if the drive is "correct" and is the same drive
  which belongs to this server.

- drive was replaced we have to format it - we
  support hot swapping of the drives.

IsOnline() is not meant for taking the drive offline
when it is hung, it is not useful we can let the
drive be online instead "return" errors for relevant
calls.

* return errFaultyDisk for DiskInfo() call

Co-authored-by: Harshavardhana <harsha@minio.io>

Possible future Improvements:

* Unify the REST server and local xlStorageDiskIDCheck. This would also improve stats significantly.
* Allow reads/writes to be aborted by the context.
* Add usage stats, concurrent count, blocked operations, etc.
2022-03-09 11:38:54 -08:00

270 lines
9.2 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 cmd
import (
"context"
"io"
"time"
)
// StorageAPI interface.
type StorageAPI interface {
// Stringified version of disk.
String() string
// Storage operations.
// Returns true if disk is online and its valid i.e valid format.json.
// This has nothing to do with if the drive is hung or not responding.
// For that individual storage API calls will fail properly. The purpose
// of this function is to know if the "drive" has "format.json" or not
// if it has a "format.json" then is it correct "format.json" or not.
IsOnline() bool
// Returns the last time this disk (re)-connected
LastConn() time.Time
// Indicates if disk is local or not.
IsLocal() bool
// Returns hostname if disk is remote.
Hostname() string
// Returns the entire endpoint.
Endpoint() Endpoint
// Close the disk, mark it purposefully closed, only implemented for remote disks.
Close() error
// Returns the unique 'uuid' of this disk.
GetDiskID() (string, error)
// Set a unique 'uuid' for this disk, only used when
// disk is replaced and formatted.
SetDiskID(id string)
// Returns healing information for a newly replaced disk,
// returns 'nil' once healing is complete or if the disk
// has never been replaced.
Healing() *healingTracker
DiskInfo(ctx context.Context) (info DiskInfo, err error)
NSScanner(ctx context.Context, cache dataUsageCache, updates chan<- dataUsageEntry) (dataUsageCache, error)
// Volume operations.
MakeVol(ctx context.Context, volume string) (err error)
MakeVolBulk(ctx context.Context, volumes ...string) (err error)
ListVols(ctx context.Context) (vols []VolInfo, err error)
StatVol(ctx context.Context, volume string) (vol VolInfo, err error)
DeleteVol(ctx context.Context, volume string, forceDelete bool) (err error)
// WalkDir will walk a directory on disk and return a metacache stream on wr.
WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) error
// Metadata operations
DeleteVersion(ctx context.Context, volume, path string, fi FileInfo, forceDelMarker bool) error
DeleteVersions(ctx context.Context, volume string, versions []FileInfoVersions) []error
WriteMetadata(ctx context.Context, volume, path string, fi FileInfo) error
UpdateMetadata(ctx context.Context, volume, path string, fi FileInfo) error
ReadVersion(ctx context.Context, volume, path, versionID string, readData bool) (FileInfo, error)
RenameData(ctx context.Context, srcVolume, srcPath string, fi FileInfo, dstVolume, dstPath string) error
// File operations.
ListDir(ctx context.Context, volume, dirPath string, count int) ([]string, error)
ReadFile(ctx context.Context, volume string, path string, offset int64, buf []byte, verifier *BitrotVerifier) (n int64, err error)
AppendFile(ctx context.Context, volume string, path string, buf []byte) (err error)
CreateFile(ctx context.Context, volume, path string, size int64, reader io.Reader) error
ReadFileStream(ctx context.Context, volume, path string, offset, length int64) (io.ReadCloser, error)
RenameFile(ctx context.Context, srcVolume, srcPath, dstVolume, dstPath string) error
CheckParts(ctx context.Context, volume string, path string, fi FileInfo) error
Delete(ctx context.Context, volume string, path string, recursive bool) (err error)
VerifyFile(ctx context.Context, volume, path string, fi FileInfo) error
StatInfoFile(ctx context.Context, volume, path string, glob bool) (stat []StatInfo, err error)
// Write all data, syncs the data to disk.
// Should be used for smaller payloads.
WriteAll(ctx context.Context, volume string, path string, b []byte) (err error)
// Read all.
ReadAll(ctx context.Context, volume string, path string) (buf []byte, err error)
GetDiskLoc() (poolIdx, setIdx, diskIdx int) // Retrieve location indexes.
SetDiskLoc(poolIdx, setIdx, diskIdx int) // Set location indexes.
}
type unrecognizedDisk struct {
storage StorageAPI
}
func (p *unrecognizedDisk) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) String() string {
return p.storage.String()
}
func (p *unrecognizedDisk) IsOnline() bool {
return false
}
func (p *unrecognizedDisk) LastConn() time.Time {
return p.storage.LastConn()
}
func (p *unrecognizedDisk) IsLocal() bool {
return p.storage.IsLocal()
}
func (p *unrecognizedDisk) Endpoint() Endpoint {
return p.storage.Endpoint()
}
func (p *unrecognizedDisk) Hostname() string {
return p.storage.Hostname()
}
func (p *unrecognizedDisk) Healing() *healingTracker {
return nil
}
func (p *unrecognizedDisk) NSScanner(ctx context.Context, cache dataUsageCache, updates chan<- dataUsageEntry) (dataUsageCache, error) {
return dataUsageCache{}, errDiskNotFound
}
func (p *unrecognizedDisk) GetDiskLoc() (poolIdx, setIdx, diskIdx int) {
return -1, -1, -1
}
func (p *unrecognizedDisk) SetDiskLoc(poolIdx, setIdx, diskIdx int) {
}
func (p *unrecognizedDisk) Close() error {
return p.storage.Close()
}
func (p *unrecognizedDisk) GetDiskID() (string, error) {
return "", errDiskNotFound
}
func (p *unrecognizedDisk) SetDiskID(id string) {
}
func (p *unrecognizedDisk) DiskInfo(ctx context.Context) (info DiskInfo, err error) {
return info, errDiskNotFound
}
func (p *unrecognizedDisk) MakeVolBulk(ctx context.Context, volumes ...string) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) MakeVol(ctx context.Context, volume string) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) ListVols(ctx context.Context) ([]VolInfo, error) {
return nil, errDiskNotFound
}
func (p *unrecognizedDisk) StatVol(ctx context.Context, volume string) (vol VolInfo, err error) {
return vol, errDiskNotFound
}
func (p *unrecognizedDisk) DeleteVol(ctx context.Context, volume string, forceDelete bool) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) ListDir(ctx context.Context, volume, dirPath string, count int) ([]string, error) {
return nil, errDiskNotFound
}
func (p *unrecognizedDisk) ReadFile(ctx context.Context, volume string, path string, offset int64, buf []byte, verifier *BitrotVerifier) (n int64, err error) {
return 0, errDiskNotFound
}
func (p *unrecognizedDisk) AppendFile(ctx context.Context, volume string, path string, buf []byte) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) CreateFile(ctx context.Context, volume, path string, size int64, reader io.Reader) error {
return errDiskNotFound
}
func (p *unrecognizedDisk) ReadFileStream(ctx context.Context, volume, path string, offset, length int64) (io.ReadCloser, error) {
return nil, errDiskNotFound
}
func (p *unrecognizedDisk) RenameFile(ctx context.Context, srcVolume, srcPath, dstVolume, dstPath string) error {
return errDiskNotFound
}
func (p *unrecognizedDisk) RenameData(ctx context.Context, srcVolume, srcPath string, fi FileInfo, dstVolume, dstPath string) error {
return errDiskNotFound
}
func (p *unrecognizedDisk) CheckParts(ctx context.Context, volume string, path string, fi FileInfo) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) Delete(ctx context.Context, volume string, path string, recursive bool) (err error) {
return errDiskNotFound
}
// DeleteVersions deletes slice of versions, it can be same object
// or multiple objects.
func (p *unrecognizedDisk) DeleteVersions(ctx context.Context, volume string, versions []FileInfoVersions) (errs []error) {
errs = make([]error, len(versions))
for i := range errs {
errs[i] = errDiskNotFound
}
return errs
}
func (p *unrecognizedDisk) VerifyFile(ctx context.Context, volume, path string, fi FileInfo) error {
return errDiskNotFound
}
func (p *unrecognizedDisk) WriteAll(ctx context.Context, volume string, path string, b []byte) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) DeleteVersion(ctx context.Context, volume, path string, fi FileInfo, forceDelMarker bool) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) UpdateMetadata(ctx context.Context, volume, path string, fi FileInfo) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) WriteMetadata(ctx context.Context, volume, path string, fi FileInfo) (err error) {
return errDiskNotFound
}
func (p *unrecognizedDisk) ReadVersion(ctx context.Context, volume, path, versionID string, readData bool) (fi FileInfo, err error) {
return fi, errDiskNotFound
}
func (p *unrecognizedDisk) ReadAll(ctx context.Context, volume string, path string) (buf []byte, err error) {
return nil, errDiskNotFound
}
func (p *unrecognizedDisk) StatInfoFile(ctx context.Context, volume, path string, glob bool) (stat []StatInfo, err error) {
return nil, errDiskNotFound
}