minio/cmd/endpoint-ellipses.go
2020-07-14 09:38:05 -07:00

398 lines
12 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018-2020 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"fmt"
"sort"
"strconv"
"strings"
"github.com/minio/minio-go/v7/pkg/set"
"github.com/minio/minio/cmd/config"
"github.com/minio/minio/pkg/ellipses"
"github.com/minio/minio/pkg/env"
)
// This file implements and supports ellipses pattern for
// `minio server` command line arguments.
// Endpoint set represents parsed ellipses values, also provides
// methods to get the sets of endpoints.
type endpointSet struct {
argPatterns []ellipses.ArgPattern
endpoints []string // Endpoints saved from previous GetEndpoints().
setIndexes [][]uint64 // All the sets.
}
// Supported set sizes this is used to find the optimal
// single set size.
var setSizes = []uint64{4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
// getDivisibleSize - returns a greatest common divisor of
// all the ellipses sizes.
func getDivisibleSize(totalSizes []uint64) (result uint64) {
gcd := func(x, y uint64) uint64 {
for y != 0 {
x, y = y, x%y
}
return x
}
result = totalSizes[0]
for i := 1; i < len(totalSizes); i++ {
result = gcd(result, totalSizes[i])
}
return result
}
// isValidSetSize - checks whether given count is a valid set size for erasure coding.
var isValidSetSize = func(count uint64) bool {
return (count >= setSizes[0] && count <= setSizes[len(setSizes)-1])
}
func commonSetDriveCount(divisibleSize uint64, setCounts []uint64) (setSize uint64) {
// prefers setCounts to be sorted for optimal behavior.
if divisibleSize < setCounts[len(setCounts)-1] {
return divisibleSize
}
// Figure out largest value of total_drives_in_erasure_set which results
// in least number of total_drives/total_drives_erasure_set ratio.
prevD := divisibleSize / setCounts[0]
for _, cnt := range setCounts {
if divisibleSize%cnt == 0 {
d := divisibleSize / cnt
if d <= prevD {
prevD = d
setSize = cnt
}
}
}
return setSize
}
// possibleSetCountsWithSymmetry returns symmetrical setCounts based on the
// input argument patterns, the symmetry calculation is to ensure that
// we also use uniform number of drives common across all ellipses patterns.
func possibleSetCountsWithSymmetry(setCounts []uint64, argPatterns []ellipses.ArgPattern) []uint64 {
var newSetCounts = make(map[uint64]struct{})
for _, ss := range setCounts {
var symmetry bool
for _, argPattern := range argPatterns {
for _, p := range argPattern {
if uint64(len(p.Seq)) > ss {
symmetry = uint64(len(p.Seq))%ss == 0
} else {
symmetry = ss%uint64(len(p.Seq)) == 0
}
}
}
// With no arg patterns, it is expected that user knows
// the right symmetry, so either ellipses patterns are
// provided (recommended) or no ellipses patterns.
if _, ok := newSetCounts[ss]; !ok && (symmetry || argPatterns == nil) {
newSetCounts[ss] = struct{}{}
}
}
setCounts = []uint64{}
for setCount := range newSetCounts {
setCounts = append(setCounts, setCount)
}
// Not necessarily needed but it ensures to the readers
// eyes that we prefer a sorted setCount slice for the
// subsequent function to figure out the right common
// divisor, it avoids loops.
sort.Slice(setCounts, func(i, j int) bool {
return setCounts[i] < setCounts[j]
})
return setCounts
}
// getSetIndexes returns list of indexes which provides the set size
// on each index, this function also determines the final set size
// The final set size has the affinity towards choosing smaller
// indexes (total sets)
func getSetIndexes(args []string, totalSizes []uint64, customSetDriveCount uint64, argPatterns []ellipses.ArgPattern) (setIndexes [][]uint64, err error) {
if len(totalSizes) == 0 || len(args) == 0 {
return nil, errInvalidArgument
}
setIndexes = make([][]uint64, len(totalSizes))
for _, totalSize := range totalSizes {
// Check if totalSize has minimum range upto setSize
if totalSize < setSizes[0] || totalSize < customSetDriveCount {
msg := fmt.Sprintf("Incorrect number of endpoints provided %s", args)
return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
}
}
commonSize := getDivisibleSize(totalSizes)
possibleSetCounts := func(setSize uint64) (ss []uint64) {
for _, s := range setSizes {
if setSize%s == 0 {
ss = append(ss, s)
}
}
return ss
}
setCounts := possibleSetCounts(commonSize)
if len(setCounts) == 0 {
msg := fmt.Sprintf("Incorrect number of endpoints provided %s, number of disks %d is not divisible by any supported erasure set sizes %d", args, commonSize, setSizes)
return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
}
var setSize uint64
// Custom set drive count allows to override automatic distribution.
// only meant if you want to further optimize drive distribution.
if customSetDriveCount > 0 {
msg := fmt.Sprintf("Invalid set drive count. Acceptable values for %d number drives are %d", commonSize, setCounts)
var found bool
for _, ss := range setCounts {
if ss == customSetDriveCount {
found = true
}
}
if !found {
return nil, config.ErrInvalidErasureSetSize(nil).Msg(msg)
}
// No automatic symmetry calculation expected, user is on their own
setSize = customSetDriveCount
globalCustomErasureDriveCount = true
} else {
// Returns possible set counts with symmetry.
setCounts = possibleSetCountsWithSymmetry(setCounts, argPatterns)
if len(setCounts) == 0 {
msg := fmt.Sprintf("No symmetric distribution detected with input endpoints provided %s, disks %d cannot be spread symmetrically by any supported erasure set sizes %d", args, commonSize, setSizes)
return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
}
// Final set size with all the symmetry accounted for.
setSize = commonSetDriveCount(commonSize, setCounts)
}
// Check whether setSize is with the supported range.
if !isValidSetSize(setSize) {
msg := fmt.Sprintf("Incorrect number of endpoints provided %s, number of disks %d is not divisible by any supported erasure set sizes %d", args, commonSize, setSizes)
return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
}
for i := range totalSizes {
for j := uint64(0); j < totalSizes[i]/setSize; j++ {
setIndexes[i] = append(setIndexes[i], setSize)
}
}
return setIndexes, nil
}
// Returns all the expanded endpoints, each argument is expanded separately.
func (s endpointSet) getEndpoints() (endpoints []string) {
if len(s.endpoints) != 0 {
return s.endpoints
}
for _, argPattern := range s.argPatterns {
for _, lbls := range argPattern.Expand() {
endpoints = append(endpoints, strings.Join(lbls, ""))
}
}
s.endpoints = endpoints
return endpoints
}
// Get returns the sets representation of the endpoints
// this function also intelligently decides on what will
// be the right set size etc.
func (s endpointSet) Get() (sets [][]string) {
var k = uint64(0)
endpoints := s.getEndpoints()
for i := range s.setIndexes {
for j := range s.setIndexes[i] {
sets = append(sets, endpoints[k:s.setIndexes[i][j]+k])
k = s.setIndexes[i][j] + k
}
}
return sets
}
// Return the total size for each argument patterns.
func getTotalSizes(argPatterns []ellipses.ArgPattern) []uint64 {
var totalSizes []uint64
for _, argPattern := range argPatterns {
var totalSize uint64 = 1
for _, p := range argPattern {
totalSize = totalSize * uint64(len(p.Seq))
}
totalSizes = append(totalSizes, totalSize)
}
return totalSizes
}
// Parses all arguments and returns an endpointSet which is a collection
// of endpoints following the ellipses pattern, this is what is used
// by the object layer for initializing itself.
func parseEndpointSet(customSetDriveCount uint64, args ...string) (ep endpointSet, err error) {
var argPatterns = make([]ellipses.ArgPattern, len(args))
for i, arg := range args {
patterns, perr := ellipses.FindEllipsesPatterns(arg)
if perr != nil {
return endpointSet{}, config.ErrInvalidErasureEndpoints(nil).Msg(perr.Error())
}
argPatterns[i] = patterns
}
ep.setIndexes, err = getSetIndexes(args, getTotalSizes(argPatterns), customSetDriveCount, argPatterns)
if err != nil {
return endpointSet{}, config.ErrInvalidErasureEndpoints(nil).Msg(err.Error())
}
ep.argPatterns = argPatterns
return ep, nil
}
// GetAllSets - parses all ellipses input arguments, expands them into
// corresponding list of endpoints chunked evenly in accordance with a
// specific set size.
// For example: {1...64} is divided into 4 sets each of size 16.
// This applies to even distributed setup syntax as well.
func GetAllSets(customSetDriveCount uint64, args ...string) ([][]string, error) {
var setArgs [][]string
if !ellipses.HasEllipses(args...) {
var setIndexes [][]uint64
// Check if we have more one args.
if len(args) > 1 {
var err error
setIndexes, err = getSetIndexes(args, []uint64{uint64(len(args))}, customSetDriveCount, nil)
if err != nil {
return nil, err
}
} else {
// We are in FS setup, proceed forward.
setIndexes = [][]uint64{{uint64(len(args))}}
}
s := endpointSet{
endpoints: args,
setIndexes: setIndexes,
}
setArgs = s.Get()
} else {
s, err := parseEndpointSet(customSetDriveCount, args...)
if err != nil {
return nil, err
}
setArgs = s.Get()
}
uniqueArgs := set.NewStringSet()
for _, sargs := range setArgs {
for _, arg := range sargs {
if uniqueArgs.Contains(arg) {
return nil, config.ErrInvalidErasureEndpoints(nil).Msg(fmt.Sprintf("Input args (%s) has duplicate ellipses", args))
}
uniqueArgs.Add(arg)
}
}
return setArgs, nil
}
// Override set drive count for manual distribution.
const (
EnvErasureSetDriveCount = "MINIO_ERASURE_SET_DRIVE_COUNT"
)
var (
globalCustomErasureDriveCount = false
)
// CreateServerEndpoints - validates and creates new endpoints from input args, supports
// both ellipses and without ellipses transparently.
func createServerEndpoints(serverAddr string, args ...string) (
endpointZones EndpointZones, setDriveCount int,
setupType SetupType, err error) {
if len(args) == 0 {
return nil, -1, -1, errInvalidArgument
}
if v := env.Get(EnvErasureSetDriveCount, ""); v != "" {
setDriveCount, err = strconv.Atoi(v)
if err != nil {
return nil, -1, -1, config.ErrInvalidErasureSetSize(err)
}
}
if !ellipses.HasEllipses(args...) {
setArgs, err := GetAllSets(uint64(setDriveCount), args...)
if err != nil {
return nil, -1, -1, err
}
endpointList, newSetupType, err := CreateEndpoints(serverAddr, false, setArgs...)
if err != nil {
return nil, -1, -1, err
}
endpointZones = append(endpointZones, ZoneEndpoints{
SetCount: len(setArgs),
DrivesPerSet: len(setArgs[0]),
Endpoints: endpointList,
})
setupType = newSetupType
return endpointZones, len(setArgs[0]), setupType, nil
}
var prevSetupType SetupType
var foundPrevLocal bool
for _, arg := range args {
setArgs, err := GetAllSets(uint64(setDriveCount), arg)
if err != nil {
return nil, -1, -1, err
}
var endpointList Endpoints
endpointList, setupType, err = CreateEndpoints(serverAddr, foundPrevLocal, setArgs...)
if err != nil {
return nil, -1, -1, err
}
if setDriveCount != 0 && setDriveCount != len(setArgs[0]) {
return nil, -1, -1, fmt.Errorf("All zones should have same drive per set ratio - expected %d, got %d", setDriveCount, len(setArgs[0]))
}
if prevSetupType != UnknownSetupType && prevSetupType != setupType {
return nil, -1, -1, fmt.Errorf("All zones should be of the same setup-type to maintain the original SLA expectations - expected %s, got %s", prevSetupType, setupType)
}
if err = endpointZones.Add(ZoneEndpoints{
SetCount: len(setArgs),
DrivesPerSet: len(setArgs[0]),
Endpoints: endpointList,
}); err != nil {
return nil, -1, -1, err
}
foundPrevLocal = endpointList.atleastOneEndpointLocal()
if setDriveCount == 0 {
setDriveCount = len(setArgs[0])
}
prevSetupType = setupType
}
return endpointZones, setDriveCount, setupType, nil
}