diff --git a/models/repo_list.go b/models/repo_list.go
index 1e06f2511..74bc25619 100644
--- a/models/repo_list.go
+++ b/models/repo_list.go
@@ -12,6 +12,7 @@ import (
 	"code.gitea.io/gitea/modules/util"
 
 	"xorm.io/builder"
+	"xorm.io/xorm"
 )
 
 // RepositoryListDefaultPageSize is the default number of repositories
@@ -363,6 +364,35 @@ func SearchRepository(opts *SearchRepoOptions) (RepositoryList, int64, error) {
 
 // SearchRepositoryByCondition search repositories by condition
 func SearchRepositoryByCondition(opts *SearchRepoOptions, cond builder.Cond, loadAttributes bool) (RepositoryList, int64, error) {
+	sess, count, err := searchRepositoryByCondition(opts, cond)
+	if err != nil {
+		return nil, 0, err
+	}
+	defer sess.Close()
+
+	defaultSize := 50
+	if opts.PageSize > 0 {
+		defaultSize = opts.PageSize
+	}
+	repos := make(RepositoryList, 0, defaultSize)
+	if err := sess.Find(&repos); err != nil {
+		return nil, 0, fmt.Errorf("Repo: %v", err)
+	}
+
+	if opts.PageSize <= 0 {
+		count = int64(len(repos))
+	}
+
+	if loadAttributes {
+		if err := repos.loadAttributes(sess); err != nil {
+			return nil, 0, fmt.Errorf("LoadAttributes: %v", err)
+		}
+	}
+
+	return repos, count, nil
+}
+
+func searchRepositoryByCondition(opts *SearchRepoOptions, cond builder.Cond) (*xorm.Session, int64, error) {
 	if opts.Page <= 0 {
 		opts.Page = 1
 	}
@@ -376,31 +406,24 @@ func SearchRepositoryByCondition(opts *SearchRepoOptions, cond builder.Cond, loa
 	}
 
 	sess := x.NewSession()
-	defer sess.Close()
 
-	count, err := sess.
-		Where(cond).
-		Count(new(Repository))
-	if err != nil {
-		return nil, 0, fmt.Errorf("Count: %v", err)
+	var count int64
+	if opts.PageSize > 0 {
+		var err error
+		count, err = sess.
+			Where(cond).
+			Count(new(Repository))
+		if err != nil {
+			_ = sess.Close()
+			return nil, 0, fmt.Errorf("Count: %v", err)
+		}
 	}
 
-	repos := make(RepositoryList, 0, opts.PageSize)
 	sess.Where(cond).OrderBy(opts.OrderBy.String())
 	if opts.PageSize > 0 {
 		sess.Limit(opts.PageSize, (opts.Page-1)*opts.PageSize)
 	}
-	if err = sess.Find(&repos); err != nil {
-		return nil, 0, fmt.Errorf("Repo: %v", err)
-	}
-
-	if loadAttributes {
-		if err = repos.loadAttributes(sess); err != nil {
-			return nil, 0, fmt.Errorf("LoadAttributes: %v", err)
-		}
-	}
-
-	return repos, count, nil
+	return sess, count, nil
 }
 
 // accessibleRepositoryCondition takes a user a returns a condition for checking if a repository is accessible
@@ -456,6 +479,33 @@ func SearchRepositoryByName(opts *SearchRepoOptions) (RepositoryList, int64, err
 	return SearchRepository(opts)
 }
 
+// SearchRepositoryIDs takes keyword and part of repository name to search,
+// it returns results in given range and number of total results.
+func SearchRepositoryIDs(opts *SearchRepoOptions) ([]int64, int64, error) {
+	opts.IncludeDescription = false
+
+	cond := SearchRepositoryCondition(opts)
+
+	sess, count, err := searchRepositoryByCondition(opts, cond)
+	if err != nil {
+		return nil, 0, err
+	}
+	defer sess.Close()
+
+	defaultSize := 50
+	if opts.PageSize > 0 {
+		defaultSize = opts.PageSize
+	}
+
+	ids := make([]int64, 0, defaultSize)
+	err = sess.Select("id").Table("repository").Find(&ids)
+	if opts.PageSize <= 0 {
+		count = int64(len(ids))
+	}
+
+	return ids, count, err
+}
+
 // AccessibleRepoIDsQuery queries accessible repository ids. Usable as a subquery wherever repo ids need to be filtered.
 func AccessibleRepoIDsQuery(user *User) *builder.Builder {
 	// NB: Please note this code needs to still work if user is nil
diff --git a/routers/api/v1/repo/issue.go b/routers/api/v1/repo/issue.go
index 17dad9794..683a2a43b 100644
--- a/routers/api/v1/repo/issue.go
+++ b/routers/api/v1/repo/issue.go
@@ -16,7 +16,6 @@ import (
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/convert"
 	issue_indexer "code.gitea.io/gitea/modules/indexer/issues"
-	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/notification"
 	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
@@ -113,11 +112,7 @@ func SearchIssues(ctx *context.APIContext) {
 	}
 
 	// find repos user can access (for issue search)
-	repoIDs := make([]int64, 0)
 	opts := &models.SearchRepoOptions{
-		ListOptions: models.ListOptions{
-			PageSize: 15,
-		},
 		Private:     false,
 		AllPublic:   true,
 		TopicOnly:   false,
@@ -132,21 +127,10 @@ func SearchIssues(ctx *context.APIContext) {
 		opts.AllLimited = true
 	}
 
-	for page := 1; ; page++ {
-		opts.Page = page
-		repos, count, err := models.SearchRepositoryByName(opts)
-		if err != nil {
-			ctx.Error(http.StatusInternalServerError, "SearchRepositoryByName", err)
-			return
-		}
-
-		if len(repos) == 0 {
-			break
-		}
-		log.Trace("Processing next %d repos of %d", len(repos), count)
-		for _, repo := range repos {
-			repoIDs = append(repoIDs, repo.ID)
-		}
+	repoIDs, _, err := models.SearchRepositoryIDs(opts)
+	if err != nil {
+		ctx.Error(http.StatusInternalServerError, "SearchRepositoryByName", err)
+		return
 	}
 
 	var issues []*models.Issue