From 2ac42b70cee345315a313168ad8f735dc0780dbc Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <evgeniy@morphbits.ru>
Date: Wed, 5 Oct 2022 11:09:53 +0300
Subject: [PATCH] [#1826] services/object: Parallelize object search

Signed-off-by: Evgenii Stratonikov <evgeniy@morphbits.ru>
---
 pkg/services/object/search/container.go | 55 +++++++++++++++++++------
 pkg/services/object/search/exec.go      | 16 -------
 pkg/services/object/search/remote.go    | 29 -------------
 pkg/services/object/search/service.go   |  2 +
 4 files changed, 45 insertions(+), 57 deletions(-)
 delete mode 100644 pkg/services/object/search/remote.go

diff --git a/pkg/services/object/search/container.go b/pkg/services/object/search/container.go
index 61ff94025..5c238cde9 100644
--- a/pkg/services/object/search/container.go
+++ b/pkg/services/object/search/container.go
@@ -2,6 +2,8 @@ package searchsvc
 
 import (
 	"context"
+	"encoding/hex"
+	"sync"
 
 	"github.com/nspcc-dev/neofs-node/pkg/core/client"
 	"go.uber.org/zap"
@@ -65,24 +67,53 @@ func (exec *execCtx) processCurrentEpoch() bool {
 			break
 		}
 
+		var wg sync.WaitGroup
+		var mtx sync.Mutex
+
 		for i := range addrs {
-			select {
-			case <-ctx.Done():
-				exec.log.Debug("interrupt placement iteration by context",
-					zap.String("error", ctx.Err().Error()),
-				)
+			wg.Add(1)
+			go func(i int) {
+				defer wg.Done()
+				select {
+				case <-ctx.Done():
+					exec.log.Debug("interrupt placement iteration by context",
+						zap.String("error", ctx.Err().Error()))
+					return
+				default:
+				}
 
-				return true
-			default:
-			}
+				var info client.NodeInfo
 
-			// TODO: #1142 consider parallel execution
-			var info client.NodeInfo
+				client.NodeInfoFromNetmapElement(&info, addrs[i])
 
-			client.NodeInfoFromNetmapElement(&info, addrs[i])
+				exec.log.Debug("processing node...", zap.String("key", hex.EncodeToString(addrs[i].PublicKey())))
 
-			exec.processNode(ctx, info)
+				c, err := exec.svc.clientConstructor.get(info)
+				if err != nil {
+					mtx.Lock()
+					exec.status = statusUndefined
+					exec.err = err
+					mtx.Unlock()
+
+					exec.log.Debug("could not construct remote node client")
+					return
+				}
+
+				ids, err := c.searchObjects(exec, info)
+				if err != nil {
+					exec.log.Debug("remote operation failed",
+						zap.String("error", err.Error()))
+
+					return
+				}
+
+				mtx.Lock()
+				exec.writeIDList(ids)
+				mtx.Unlock()
+			}(i)
 		}
+
+		wg.Wait()
 	}
 
 	return false
diff --git a/pkg/services/object/search/exec.go b/pkg/services/object/search/exec.go
index 97b5dc270..4e7100f09 100644
--- a/pkg/services/object/search/exec.go
+++ b/pkg/services/object/search/exec.go
@@ -3,7 +3,6 @@ package searchsvc
 import (
 	"context"
 
-	"github.com/nspcc-dev/neofs-node/pkg/core/client"
 	"github.com/nspcc-dev/neofs-node/pkg/services/object_manager/placement"
 	"github.com/nspcc-dev/neofs-node/pkg/util/logger"
 	cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
@@ -118,21 +117,6 @@ func (exec *execCtx) generateTraverser(cnr cid.ID) (*placement.Traverser, bool)
 	}
 }
 
-func (exec execCtx) remoteClient(info client.NodeInfo) (searchClient, bool) {
-	c, err := exec.svc.clientConstructor.get(info)
-	switch {
-	default:
-		exec.status = statusUndefined
-		exec.err = err
-
-		exec.log.Debug("could not construct remote node client")
-	case err == nil:
-		return c, true
-	}
-
-	return nil, false
-}
-
 func (exec *execCtx) writeIDList(ids []oid.ID) {
 	err := exec.prm.writer.WriteIDs(ids)
 
diff --git a/pkg/services/object/search/remote.go b/pkg/services/object/search/remote.go
deleted file mode 100644
index a51cec6dc..000000000
--- a/pkg/services/object/search/remote.go
+++ /dev/null
@@ -1,29 +0,0 @@
-package searchsvc
-
-import (
-	"context"
-
-	"github.com/nspcc-dev/neofs-node/pkg/core/client"
-	"go.uber.org/zap"
-)
-
-func (exec *execCtx) processNode(ctx context.Context, info client.NodeInfo) {
-	exec.log.Debug("processing node...")
-
-	client, ok := exec.remoteClient(info)
-	if !ok {
-		return
-	}
-
-	ids, err := client.searchObjects(exec, info)
-
-	if err != nil {
-		exec.log.Debug("remote operation failed",
-			zap.String("error", err.Error()),
-		)
-
-		return
-	}
-
-	exec.writeIDList(ids)
-}
diff --git a/pkg/services/object/search/service.go b/pkg/services/object/search/service.go
index 227c4a2bd..231c19d9e 100644
--- a/pkg/services/object/search/service.go
+++ b/pkg/services/object/search/service.go
@@ -22,6 +22,8 @@ type Service struct {
 type Option func(*cfg)
 
 type searchClient interface {
+	// searchObjects searches objects on the specified node.
+	// MUST NOT modify execCtx as it can be accessed concurrently.
 	searchObjects(*execCtx, client.NodeInfo) ([]oid.ID, error)
 }