From cbd94b18a5c86053768e4e20e43131b5ca6d19a5 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Thu, 8 Nov 2018 07:37:34 -0800
Subject: [PATCH] improve "ls -al" performance for large directory

---
 weed/command/mount_std.go |  4 +++-
 weed/filesys/dir.go       | 29 ++++++++++++++++++++++++++---
 weed/filesys/file.go      |  2 +-
 weed/filesys/wfs.go       |  7 +++++--
 4 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/weed/command/mount_std.go b/weed/command/mount_std.go
index 92dcc9008..f682eebfa 100644
--- a/weed/command/mount_std.go
+++ b/weed/command/mount_std.go
@@ -5,13 +5,14 @@ package command
 import (
 	"fmt"
 	"runtime"
+	"strings"
+	"time"
 
 	"bazil.org/fuse"
 	"bazil.org/fuse/fs"
 	"github.com/chrislusf/seaweedfs/weed/filesys"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/util"
-	"strings"
 )
 
 func runMount(cmd *Command, args []string) bool {
@@ -72,6 +73,7 @@ func runMount(cmd *Command, args []string) bool {
 		ChunkSizeLimit:     int64(*mountOptions.chunkSizeLimitMB) * 1024 * 1024,
 		DataCenter:         *mountOptions.dataCenter,
 		DirListingLimit:    *mountOptions.dirListingLimit,
+		EntryCacheTtl:      3 * time.Second,
 	}))
 	if err != nil {
 		fuse.Unmount(*mountOptions.dir)
diff --git a/weed/filesys/dir.go b/weed/filesys/dir.go
index c1fa07ab3..caeada482 100644
--- a/weed/filesys/dir.go
+++ b/weed/filesys/dir.go
@@ -70,7 +70,7 @@ func (dir *Dir) Attr(context context.Context, attr *fuse.Attr) error {
 			dir.attributes = resp.Entry.Attributes
 		}
 
-		dir.wfs.listDirectoryEntriesCache.Set(dir.Path, resp.Entry, 300*time.Millisecond)
+		dir.wfs.listDirectoryEntriesCache.Set(dir.Path, resp.Entry, dir.wfs.option.EntryCacheTtl)
 
 		return nil
 	})
@@ -210,7 +210,7 @@ func (dir *Dir) Lookup(ctx context.Context, req *fuse.LookupRequest, resp *fuse.
 
 			entry = resp.Entry
 
-			dir.wfs.listDirectoryEntriesCache.Set(path.Join(dir.Path, entry.Name), entry, 1000*time.Millisecond)
+			dir.wfs.listDirectoryEntriesCache.Set(path.Join(dir.Path, entry.Name), entry, dir.wfs.option.EntryCacheTtl)
 
 			return nil
 		})
@@ -252,6 +252,8 @@ func (dir *Dir) ReadDirAll(ctx context.Context) (ret []fuse.Dirent, err error) {
 			return fuse.EIO
 		}
 
+		cacheTtl := estimatedCacheTtl(len(resp.Entries))
+
 		for _, entry := range resp.Entries {
 			if entry.IsDirectory {
 				dirent := fuse.Dirent{Name: entry.Name, Type: fuse.DT_Dir}
@@ -260,7 +262,7 @@ func (dir *Dir) ReadDirAll(ctx context.Context) (ret []fuse.Dirent, err error) {
 				dirent := fuse.Dirent{Name: entry.Name, Type: fuse.DT_File}
 				ret = append(ret, dirent)
 			}
-			dir.wfs.listDirectoryEntriesCache.Set(path.Join(dir.Path, entry.Name), entry, 300*time.Millisecond)
+			dir.wfs.listDirectoryEntriesCache.Set(path.Join(dir.Path, entry.Name), entry, cacheTtl)
 		}
 
 		return nil
@@ -337,3 +339,24 @@ func (dir *Dir) Setattr(ctx context.Context, req *fuse.SetattrRequest, resp *fus
 	})
 
 }
+
+func estimatedCacheTtl(numEntries int) time.Duration {
+	if numEntries < 100 {
+		// 30 ms per entry
+		return 3 * time.Second
+	}
+	if numEntries < 1000 {
+		// 10 ms per entry
+		return 10 * time.Second
+	}
+	if numEntries < 10000 {
+		// 10 ms per entry
+		return 100 * time.Second
+	}
+	if numEntries < 100000 {
+		// 10 ms per entry
+		return 1000 * time.Second
+	}
+	// 2 ms per entry
+	return time.Duration(numEntries*2) * time.Millisecond
+}
diff --git a/weed/filesys/file.go b/weed/filesys/file.go
index df02fe8f2..a41d0d8e6 100644
--- a/weed/filesys/file.go
+++ b/weed/filesys/file.go
@@ -153,7 +153,7 @@ func (file *File) maybeLoadAttributes(ctx context.Context) error {
 
 				glog.V(1).Infof("file attr %v %+v: %d", file.fullpath(), file.entry.Attributes, filer2.TotalSize(file.entry.Chunks))
 
-				file.wfs.listDirectoryEntriesCache.Set(file.fullpath(), file.entry, 300*time.Millisecond)
+				file.wfs.listDirectoryEntriesCache.Set(file.fullpath(), file.entry, file.wfs.option.EntryCacheTtl)
 
 				return nil
 			})
diff --git a/weed/filesys/wfs.go b/weed/filesys/wfs.go
index fc5a9cf93..8103fd570 100644
--- a/weed/filesys/wfs.go
+++ b/weed/filesys/wfs.go
@@ -1,14 +1,16 @@
 package filesys
 
 import (
+	"fmt"
+	"sync"
+	"time"
+
 	"bazil.org/fuse"
 	"bazil.org/fuse/fs"
-	"fmt"
 	"github.com/chrislusf/seaweedfs/weed/glog"
 	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
 	"github.com/chrislusf/seaweedfs/weed/util"
 	"github.com/karlseguin/ccache"
-	"sync"
 )
 
 type Option struct {
@@ -20,6 +22,7 @@ type Option struct {
 	ChunkSizeLimit     int64
 	DataCenter         string
 	DirListingLimit    int
+	EntryCacheTtl      time.Duration
 }
 
 type WFS struct {