Files
seaweedfs/weed/shell/command_ec_encode.go
T
Chris LuandDevin 8f80dac30f ec: strict_placement option so encode only runs while guarantees hold (#11656)
* ec: strict_placement option so encode only runs while guarantees hold

Shard placement during encode was best-effort (PlaceDurabilityFirst):
when the cluster could not satisfy the per-disk caps, anti-affinity,
replica-placement or per-rack caps, the constraints were relaxed and
the volume was encoded anyway, weaker than configured. A
strict_placement option on the erasure coding task switches planning
to PlaceStrict so the volume's planning fails instead, and the encode
is retried when capacity allows the guarantee.

Also documents the resilience rule in ec.encode help: a volume
survives losing any nodes or racks holding at most parity-shards
shards between them, and how -shardReplicaPlacement's rack and node
digits bound that loss.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* ec: expose strict_placement through the plugin form and persisted task policy

The admin UI, the admin.toml maintenance mapping, and the TaskPolicy
serialization all dropped the new flag; add the bool field to
ErasureCodingTaskConfig, the worker config form, and both conversion
directions.

* shell: describe shardReplicaPlacement as requested limits, not guarantees

ec.encode places shards best-effort, so the configured rack/node caps only
bound shard loss when the final placement actually satisfies them.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

---------

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
2026-10-08 22:05:02 +08:00

220 lines
8.9 KiB
Go

package shell
import (
"flag"
"fmt"
"io"
"strings"
"time"
"github.com/seaweedfs/seaweedfs/weed/storage/types"
"github.com/seaweedfs/seaweedfs/weed/ec"
"github.com/seaweedfs/seaweedfs/weed/glog"
"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
"github.com/seaweedfs/seaweedfs/weed/storage/erasure_coding"
"github.com/seaweedfs/seaweedfs/weed/storage/needle"
)
func init() {
Commands = append(Commands, &commandEcEncode{})
}
type commandEcEncode struct {
}
func (c *commandEcEncode) Name() string {
return "ec.encode"
}
func (c *commandEcEncode) Help() string {
return `apply erasure coding to a volume
ec.encode [-collection=""] [-fullPercent=95 -quietFor=1h] [-batchSize=10] [-verbose] [-sourceDiskType=<disk_type>] [-diskType=<disk_type>]
ec.encode [-volumeId=<volume_id>|-volumeIds=<volume_id>,...] [-batchSize=10] [-verbose] [-diskType=<disk_type>]
This command will:
1. freeze one volume
2. apply erasure coding to the volume
3. (optionally) re-balance encoded shards across multiple volume servers
The erasure coding is 10.4. So ideally you have more than 14 volume servers, and you can afford
to lose 4 volume servers.
If the number of volumes are not high, the worst case is that you only have 4 volume servers,
and the shards are spread as 4,4,3,3, respectively. You can afford to lose one volume server.
If you only have less than 4 volume servers, with erasure coding, at least you can afford to
have 4 corrupted shard files.
The guarantee follows from where shards land: a volume survives the loss of any
nodes (or racks) that hold at most parityShards (4) shards between them. Spread
is best-effort; -shardReplicaPlacement requests limits: its rack digit
sets the requested shards per rack, and its node digit the requested shards
per node (the data-center digit is not used for EC). For example
-shardReplicaPlacement=021 requests at most 1 shard per node and 2 per rack.
Only when the final placement meets these limits does losing one rack cost
at most 2 shards; the command does not guarantee that the limits are met.
The -collection parameter is a comma-separated list of collection names, with
"*" and "?" wildcards, and regex patterns:
- One collection: ec.encode -collection="mybucket"
- Several collections: ec.encode -collection="mybucket,otherbucket"
- Match by prefix: ec.encode -collection="bucket*"
- Match all collections: ec.encode -collection="*"
- The empty-named collection: ec.encode -collection="_default"
Options:
-verbose: show detailed reasons why volumes are not selected for encoding
-sourceDiskType: filter source volumes by disk type (hdd, ssd, or empty for all)
-diskType: target disk type for EC shards (hdd, ssd, or empty for default hdd)
-batchSize: encode/rebalance/verify/delete this many volumes at a time (default 10; 0 = all in one batch)
-volumeIds: comma-separated volume IDs to encode
Each batch is committed independently. If a later batch fails, earlier batches
are already encoded and their original volumes deleted.
Examples:
# Encode SSD volumes to SSD EC shards (same tier)
ec.encode -collection=mybucket -sourceDiskType=ssd -diskType=ssd
# Encode SSD volumes to HDD EC shards (tier migration to cheaper storage)
ec.encode -collection=mybucket -sourceDiskType=ssd -diskType=hdd
# Encode all volumes to SSD EC shards
ec.encode -collection=mybucket -diskType=ssd
# Encode selected volume IDs and delete originals after each batch
ec.encode -volumeIds=101,102,103 -batchSize=2
Re-balancing algorithm:
` + ecBalanceAlgorithmDescription
}
func (c *commandEcEncode) HasTag(CommandTag) bool {
return false
}
func (c *commandEcEncode) Do(args []string, commandEnv *CommandEnv, writer io.Writer) (err error) {
encodeCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
volumeId := encodeCommand.Int("volumeId", 0, "the volume id")
volumeIdsStr := encodeCommand.String("volumeIds", "", "comma-separated volume ids")
collection := encodeCommand.String("collection", "", "comma-separated collection names, wildcards, or regex patterns; empty matches the collection with no name")
fullPercentage := encodeCommand.Float64("fullPercent", 95, "the volume reaches the percentage of max volume size")
quietPeriod := encodeCommand.Duration("quietFor", time.Hour, "select volumes without no writes for this period")
maxParallelization := encodeCommand.Int("maxParallelization", DefaultMaxParallelization, "run up to X tasks in parallel, whenever possible")
batchSize := encodeCommand.Int("batchSize", DefaultEcBatchSize, "encode/re-balance/verify/delete up to this many volumes at a time (0 = all in one batch)")
forceChanges := encodeCommand.Bool("force", false, "force the encoding even if the cluster has less than recommended 4 nodes")
shardReplicaPlacement := encodeCommand.String("shardReplicaPlacement", "", "replica placement for EC shards, or master default if empty")
sourceDiskTypeStr := encodeCommand.String("sourceDiskType", "", "filter source volumes by disk type (hdd, ssd, or empty for all)")
diskTypeStr := encodeCommand.String("diskType", "", "target disk type for EC shards (hdd, ssd, or empty for default hdd)")
applyBalancing := encodeCommand.Bool("rebalance", true, "re-balance EC shards after creation (default: true)")
verbose := encodeCommand.Bool("verbose", false, "show detailed reasons why volumes are not selected for encoding")
if err = encodeCommand.Parse(args); err != nil {
return nil
}
if err = commandEnv.confirmIsLocked(args); err != nil {
return
}
rp, err := parseReplicaPlacementArg(commandEnv, *shardReplicaPlacement)
if err != nil {
return err
}
// Parse source disk type filter (optional)
var sourceDiskType *types.DiskType
if *sourceDiskTypeStr != "" {
sdt := types.ToDiskType(*sourceDiskTypeStr)
sourceDiskType = &sdt
}
// Parse target disk type for EC shards
diskType := types.ToDiskType(*diskTypeStr)
// collect topology information
topologyInfo, _, err := collectTopologyInfo(commandEnv, 0)
if err != nil {
return err
}
if !*forceChanges {
var nodeCount int
eachDataNode(topologyInfo, func(dc DataCenterId, rack RackId, dn *master_pb.DataNodeInfo) {
nodeCount++
})
if nodeCount < erasure_coding.ParityShardsCount {
glog.V(0).Infof("skip erasure coding with %d nodes, less than recommended %d nodes", nodeCount, erasure_coding.ParityShardsCount)
return nil
}
}
var volumeIds []needle.VolumeId
if *volumeId != 0 || strings.TrimSpace(*volumeIdsStr) != "" {
if *volumeId != 0 && strings.TrimSpace(*volumeIdsStr) != "" {
return fmt.Errorf("-volumeId and -volumeIds are mutually exclusive")
}
if *volumeId != 0 {
volumeIds = append(volumeIds, needle.VolumeId(*volumeId))
} else {
volumeIds, err = parseVolumeIdsFlag(*volumeIdsStr)
if err != nil {
return err
}
}
} else {
// apply to all volumes for the given collection pattern (regex)
volumeIds, _, err = collectVolumeIdsForEcEncode(commandEnv, *collection, sourceDiskType, *fullPercentage, *quietPeriod, *verbose)
if err != nil {
return err
}
}
if len(volumeIds) == 0 {
fmt.Println("No volumes, nothing to do.")
return nil
}
if *batchSize < 0 {
return fmt.Errorf("-batchSize must be >= 0")
}
batches := ec.ChunkVolumeIds(volumeIds, *batchSize)
if len(batches) > 1 {
fmt.Printf("Processing %d volumes in %d batch(es), batchSize=%d\n", len(volumeIds), len(batches), *batchSize)
}
for i, batchVolumeIds := range batches {
if len(batches) > 1 {
fmt.Printf("Starting EC encoding batch %d/%d with %d volumes: %v\n", i+1, len(batches), len(batchVolumeIds), batchVolumeIds)
}
if err := ec.ProcessEcEncodeBatch(commandEnv.ecEnv(), writer, batchVolumeIds, rp, diskType, *maxParallelization, *applyBalancing, *collection); err != nil {
return fmt.Errorf("ec encode batch %d/%d for volumes %v: %w", i+1, len(batches), batchVolumeIds, err)
}
}
if len(batches) > 1 {
fmt.Printf("Successfully completed EC encoding for %d volumes in %d batch(es)\n", len(volumeIds), len(batches))
}
return nil
}
func collectVolumeIdsForEcEncode(commandEnv *CommandEnv, collectionPattern string, sourceDiskType *types.DiskType, fullPercentage float64, quietPeriod time.Duration, verbose bool) (vids []needle.VolumeId, matchedCollections []string, err error) {
// compile regex pattern for collection matching
collectionMatcher, err := compileCollectionPattern(collectionPattern)
if err != nil {
return nil, nil, fmt.Errorf("invalid collection pattern '%s': %v", collectionPattern, err)
}
// collect topology information
topologyInfo, volumeSizeLimitMb, err := collectTopologyInfo(commandEnv, 0)
if err != nil {
return
}
quietSeconds := int64(quietPeriod / time.Second)
nowUnixSeconds := time.Now().Unix()
fmt.Printf("collect volumes with collection pattern '%s', quiet for: %d seconds and %.1f%% full\n", collectionPattern, quietSeconds, fullPercentage)
vids, matchedCollections = ec.SelectVolumeIdsFromTopology(topologyInfo, volumeSizeLimitMb, collectionMatcher, sourceDiskType, quietSeconds, nowUnixSeconds, fullPercentage, verbose)
return
}