Files
seaweedfs/weed/mount/inode_to_path_test.go
T
Chris LuandGitHub f475d60fcf mount: move directory cache state to a side map to shrink InodeEntry (152 to 32 bytes) (#10114)
mount: move directory cache state to a side map to shrink InodeEntry

The mount keeps an InodeEntry alive for every inode the kernel references.
On a mount that is almost entirely regular files, each entry carried the full
directory readdir-cache bookkeeping (four time.Time fields plus counters),
bloating it to 152 bytes whether or not the inode was a directory.

Move that state into a dirState held in a side map keyed by inode, and drop the
isDirectory bool: an inode is a directory iff it has a dirState. InodeEntry is
now just paths + nlookup at 32 bytes, landing in a smaller Go allocator size
class; on a mount with tens of millions of cached file inodes that is several GB
less resident heap. As a side effect the readdir-cache scan helpers iterate only
directories instead of every inode.
2026-06-25 19:17:32 -07:00

168 lines
4.1 KiB
Go

package mount
import (
"testing"
"time"
"github.com/seaweedfs/seaweedfs/weed/util"
)
func TestInodeEntry_removeOnePath(t *testing.T) {
tests := []struct {
name string
entry InodeEntry
p util.FullPath
want bool
count int
}{
{
name: "actual case",
entry: InodeEntry{
paths: []util.FullPath{"/pjd/nx", "/pjd/n0"},
},
p: "/pjd/nx",
want: true,
count: 1,
},
{
name: "empty",
entry: InodeEntry{},
p: "x",
want: false,
count: 0,
},
{
name: "single",
entry: InodeEntry{
paths: []util.FullPath{"/x"},
},
p: "/x",
want: true,
count: 0,
},
{
name: "first",
entry: InodeEntry{
paths: []util.FullPath{"/x", "/y", "/z"},
},
p: "/x",
want: true,
count: 2,
},
{
name: "middle",
entry: InodeEntry{
paths: []util.FullPath{"/x", "/y", "/z"},
},
p: "/y",
want: true,
count: 2,
},
{
name: "last",
entry: InodeEntry{
paths: []util.FullPath{"/x", "/y", "/z"},
},
p: "/z",
want: true,
count: 2,
},
{
name: "not found",
entry: InodeEntry{
paths: []util.FullPath{"/x", "/y", "/z"},
},
p: "/t",
want: false,
count: 3,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
if got := tt.entry.removeOnePath(tt.p); got != tt.want {
t.Errorf("removeOnePath() = %v, want %v", got, tt.want)
}
if tt.count != len(tt.entry.paths) {
t.Errorf("removeOnePath path count = %v, want %v", len(tt.entry.paths), tt.count)
}
for i, p := range tt.entry.paths {
if p == tt.p {
t.Errorf("removeOnePath found path still exists at %v, %v", i, p)
}
}
})
}
}
// Only directory inodes carry dirState; files never do. This keeps the file
// InodeEntry in the smaller size class, which is the memory win on large mounts.
func TestOnlyDirectoriesGetDirState(t *testing.T) {
itp := NewInodeToPath(util.FullPath("/"), 60)
file := util.FullPath("/data/file.txt")
fileInode := itp.Lookup(file, time.Now().Unix(), false, false, 0, true)
if _, ok := itp.dirStates[fileInode]; ok {
t.Fatal("file inode must not have a dirState")
}
// dir queries against a file are no-ops and must not register one
itp.GetSubdirCount(file)
itp.IsChildrenCached(file)
itp.ShouldReadDirectoryDirect(file)
itp.MarkChildrenCached(file)
if _, ok := itp.dirStates[fileInode]; ok {
t.Fatal("dir queries on a file inode must not create a dirState")
}
dir := util.FullPath("/data")
dirInode := itp.Lookup(dir, time.Now().Unix(), true, false, 0, true)
if _, ok := itp.dirStates[dirInode]; !ok {
t.Fatal("directory inode should be registered in dirStates at creation")
}
// forgetting the directory drops its dirState
itp.Forget(dirInode, 1, nil)
if _, ok := itp.dirStates[dirInode]; ok {
t.Fatal("forgotten directory must be removed from dirStates")
}
}
func TestRecordDirectoryUpdateSwitchesDirectoryToReadThrough(t *testing.T) {
root := util.FullPath("/")
dir := util.FullPath("/data")
inodeToPath := NewInodeToPath(root, 60)
inodeToPath.Lookup(dir, time.Now().Unix(), true, false, 0, true)
inodeToPath.MarkChildrenCached(dir)
now := time.Now()
if !inodeToPath.RecordDirectoryUpdate(dir, now, time.Second, 1) {
t.Fatal("expected directory to switch to read-through mode")
}
if inodeToPath.IsChildrenCached(dir) {
t.Fatal("directory should no longer be marked cached")
}
if !inodeToPath.ShouldReadDirectoryDirect(dir) {
t.Fatal("directory should be served via direct reads after hot invalidation")
}
}
func TestMarkChildrenCachedClearsReadThroughMode(t *testing.T) {
root := util.FullPath("/")
dir := util.FullPath("/data")
inodeToPath := NewInodeToPath(root, 60)
inodeToPath.Lookup(dir, time.Now().Unix(), true, false, 0, true)
if !inodeToPath.MarkDirectoryReadThrough(dir, time.Now()) {
t.Fatal("expected read-through flag to be set")
}
inodeToPath.MarkChildrenCached(dir)
if !inodeToPath.IsChildrenCached(dir) {
t.Fatal("directory should be cached after MarkChildrenCached")
}
if inodeToPath.ShouldReadDirectoryDirect(dir) {
t.Fatal("directory should leave read-through mode after caching")
}
}