diff --git a/BUILD b/BUILD
index 6ace559a2..7ba93a3de 100644
--- a/BUILD
+++ b/BUILD
@@ -133,7 +133,7 @@ go_path(
         # binaries have been factored into a cli package, which is
         # a good practice in any case.
         "//runsc/cli",
-        "//shim/cli",
+        "//shim/v1/cli",
         "//webhook/pkg/cli",
         "//tools/checklocks",
 
diff --git a/nogo.yaml b/nogo.yaml
index 8d4d4eeb5..2bd5acf61 100644
--- a/nogo.yaml
+++ b/nogo.yaml
@@ -84,8 +84,8 @@ global:
       - "panic recovered: .*types/sizes.go:82: assertion failed"
     exclude:
       # Generated: exempt all.
-      - pkg/shim/runtimeoptions/runtimeoptions_cri.go
-      - pkg/shim/runtimeoptions/v14/runtimeoptions_cri.go
+      - pkg/shim/v1/runtimeoptions/runtimeoptions_cri.go
+      - pkg/shim/v1/runtimeoptions/v14/runtimeoptions_cri.go
 analyzers:
   asmdecl:
     generated: # Enabled.
diff --git a/pkg/sentry/control/state.go b/pkg/sentry/control/state.go
index 4eb7ec300..b3b284f0c 100644
--- a/pkg/sentry/control/state.go
+++ b/pkg/sentry/control/state.go
@@ -18,8 +18,6 @@ import (
 	"errors"
 	"fmt"
 
-	"gvisor.dev/gvisor/pkg/abi/linux"
-	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/pgalloc"
 	"gvisor.dev/gvisor/pkg/sentry/state"
@@ -84,18 +82,7 @@ func (s *State) Save(o *SaveOpts, _ *struct{}) error {
 		Key:                o.Key,
 		Metadata:           o.Metadata,
 		MemoryFileSaveOpts: o.MemoryFileSaveOpts,
-		Callback: func(err error) {
-			if err == nil {
-				log.Infof("Save succeeded: exiting...")
-				s.Kernel.SetSaveSuccess(false /* autosave */)
-			} else {
-				log.Warningf("Save failed: %v", err)
-				s.Kernel.SetSaveError(err)
-			}
-			if !o.Resume {
-				s.Kernel.Kill(linux.WaitStatusExit(0))
-			}
-		},
+		Resume:             o.Resume,
 	}
 	if o.HavePagesFile {
 		saveOpts.PagesMetadata, err = o.ReleaseFD(1)
diff --git a/pkg/sentry/fsimpl/gofer/save_restore.go b/pkg/sentry/fsimpl/gofer/save_restore.go
index 66bde23d1..3d1249f37 100644
--- a/pkg/sentry/fsimpl/gofer/save_restore.go
+++ b/pkg/sentry/fsimpl/gofer/save_restore.go
@@ -31,6 +31,8 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/vfs"
 )
 
+var _ vfs.FilesystemImplSaveRestoreExtension = (*filesystem)(nil)
+
 // +stateify savable
 type savedDentryRW struct {
 	read  bool
@@ -134,6 +136,11 @@ func (d *dentry) beforeSave() {
 	}
 }
 
+// BeforeResume implements vfs.FilesystemImplSaveRestoreExtension.BeforeResume.
+func (fs *filesystem) BeforeResume(ctx context.Context) {
+	fs.savedDentryRW = nil
+}
+
 // afterLoad is invoked by stateify.
 func (fs *filesystem) afterLoad(ctx goContext.Context) {
 	fs.mf = pgalloc.MemoryFileFromContext(ctx)
diff --git a/pkg/sentry/fsimpl/proc/tasks.go b/pkg/sentry/fsimpl/proc/tasks.go
index 68dac3160..4138ef19a 100644
--- a/pkg/sentry/fsimpl/proc/tasks.go
+++ b/pkg/sentry/fsimpl/proc/tasks.go
@@ -22,6 +22,7 @@ import (
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/errors/linuxerr"
+	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs"
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
@@ -68,6 +69,14 @@ var _ kernfs.Inode = (*tasksInode)(nil)
 func (fs *filesystem) newTasksInode(ctx context.Context, k *kernel.Kernel, pidns *kernel.PIDNamespace, internalData *InternalData) *tasksInode {
 	root := auth.NewRootCredentials(pidns.UserNamespace())
 
+	// /proc is expected to have inode number
+	// include/linux/proc_ns.h:PROC_ROOT_INO == 1; ensure that this is the case
+	// by generating its inode number before any of its descendants.
+	rootIno := fs.NextIno()
+	if rootIno != 1 {
+		log.Traceback("proc root inode has number %d", rootIno)
+	}
+
 	contents := map[string]kernfs.Inode{
 		"cmdline":        fs.newInode(ctx, root, 0444, &cmdLineData{}),
 		"cpuinfo":        fs.newInode(ctx, root, 0444, newStaticFileSetStat(cpuInfoData(k))),
@@ -99,7 +108,7 @@ func (fs *filesystem) newTasksInode(ctx context.Context, k *kernel.Kernel, pidns
 		fs:                    fs,
 		fakeCgroupControllers: internalData.Cgroups,
 	}
-	inode.InodeAttrs.Init(ctx, root, linux.UNNAMED_MAJOR, fs.devMinor, fs.NextIno(), linux.ModeDirectory|0555)
+	inode.InodeAttrs.Init(ctx, root, linux.UNNAMED_MAJOR, fs.devMinor, rootIno, linux.ModeDirectory|0555)
 	inode.InitRefs()
 
 	inode.OrderedChildren.Init(kernfs.OrderedChildrenOptions{})
diff --git a/pkg/sentry/fsimpl/tmpfs/save_restore.go b/pkg/sentry/fsimpl/tmpfs/save_restore.go
index 391adc968..41d6a588d 100644
--- a/pkg/sentry/fsimpl/tmpfs/save_restore.go
+++ b/pkg/sentry/fsimpl/tmpfs/save_restore.go
@@ -23,6 +23,8 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/vfs"
 )
 
+var _ vfs.FilesystemImplSaveRestoreExtension = (*filesystem)(nil)
+
 // saveMf is called by stateify.
 func (fs *filesystem) saveMf() string {
 	if !fs.mf.IsSavable() {
@@ -75,6 +77,9 @@ func (fs *filesystem) PrepareSave(ctx context.Context) error {
 	return nil
 }
 
+// BeforeResume implements vfs.FilesystemImplSaveRestoreExtension.BeforeResume.
+func (fs *filesystem) BeforeResume(ctx context.Context) {}
+
 // CompleteRestore implements
 // vfs.FilesystemImplSaveRestoreExtension.CompleteRestore.
 func (fs *filesystem) CompleteRestore(ctx context.Context, opts vfs.CompleteRestoreOptions) error {
diff --git a/pkg/sentry/hostmm/hostmm.go b/pkg/sentry/hostmm/hostmm.go
index b64b0aaeb..ec469aad9 100644
--- a/pkg/sentry/hostmm/hostmm.go
+++ b/pkg/sentry/hostmm/hostmm.go
@@ -26,23 +26,30 @@ import (
 	"gvisor.dev/gvisor/pkg/log"
 )
 
-// GetTransparentHugepageEnum returns the currently selected option for
+// ReadTransparentHugepageEnum returns the currently selected option for
 // whichever of
 // /sys/kernel/mm/transparent_hugepage/{enabled,shmem_enabled,defrag} is
 // specified by filename. (Only the basename is required, not the full path.)
-func GetTransparentHugepageEnum(filename string) (string, error) {
+func ReadTransparentHugepageEnum(filename string) (string, error) {
 	pathname := path.Join("/sys/kernel/mm/transparent_hugepage/", filename)
 	data, err := os.ReadFile(pathname)
 	if err != nil {
 		return "", err
 	}
+	return GetTransparentHugepageEnum(string(data))
+}
+
+// GetTransparentHugepageEnum returns the currently selected option given the
+// contents of any of
+// /sys/kernel/mm/transparent_hugepage/{enabled,shmem_enabled,defrag}.
+func GetTransparentHugepageEnum(data string) (string, error) {
 	// In these files, the selected option is highlighted by square brackets.
-	m := regexp.MustCompile(`\[.*\]`).Find(data)
-	if m == nil {
-		return "", fmt.Errorf("failed to parse %s: %q", pathname, data)
+	m := regexp.MustCompile(`\[.*\]`).FindString(data)
+	if m == "" {
+		return "", fmt.Errorf("failed to find selected option in %q", data)
 	}
 	// Remove the square brackets.
-	return string(m[1 : len(m)-1]), nil
+	return m[1 : len(m)-1], nil
 }
 
 // NotifyCurrentMemcgPressureCallback requests that f is called whenever the
diff --git a/pkg/sentry/kernel/kernel.go b/pkg/sentry/kernel/kernel.go
index d9e0a9c42..3effbc6d1 100644
--- a/pkg/sentry/kernel/kernel.go
+++ b/pkg/sentry/kernel/kernel.go
@@ -702,6 +702,11 @@ func (k *Kernel) SaveTo(ctx context.Context, w, pagesMetadata io.Writer, pagesFi
 	return nil
 }
 
+// BeforeResume is called before the kernel is resumed after save.
+func (k *Kernel) BeforeResume(ctx context.Context) {
+	k.vfs.BeforeResume(ctx)
+}
+
 func (k *Kernel) saveMemoryFiles(ctx context.Context, w, pagesMetadata io.Writer, pagesFile *fd.FD, mfsToSave map[string]*pgalloc.MemoryFile, mfOpts pgalloc.SaveOpts) error {
 	// Save the memory files' state.
 	memoryStart := time.Now()
diff --git a/pkg/sentry/state/state.go b/pkg/sentry/state/state.go
index 4f82ca21d..57e884441 100644
--- a/pkg/sentry/state/state.go
+++ b/pkg/sentry/state/state.go
@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"io"
 
+	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/errors/linuxerr"
 	"gvisor.dev/gvisor/pkg/fd"
@@ -68,15 +69,18 @@ type SaveOpts struct {
 	// MemoryFileSaveOpts is passed to calls to pgalloc.MemoryFile.SaveTo().
 	MemoryFileSaveOpts pgalloc.SaveOpts
 
-	// Callback is called prior to unpause, with any save error.
-	Callback func(err error)
-
 	// Resume indicates if the statefile is used for save-resume.
 	Resume bool
+
+	// Autosave indicates if the statefile is used for autosave.
+	Autosave bool
 }
 
 // Save saves the system state.
 func (opts SaveOpts) Save(ctx context.Context, k *kernel.Kernel, w *watchdog.Watchdog) error {
+	t, _ := CPUTime()
+	log.Infof("Before save CPU usage: %s", t.String())
+
 	log.Infof("Sandbox save started, pausing all tasks.")
 	k.Pause()
 	k.ReceiveTaskStates()
@@ -127,7 +131,22 @@ func (opts SaveOpts) Save(ctx context.Context, k *kernel.Kernel, w *watchdog.Wat
 			}
 		}
 	}
-	opts.Callback(err)
+
+	t1, _ := CPUTime()
+	log.Infof("Save CPU usage: %s", (t1 - t).String())
+	if err == nil {
+		log.Infof("Save succeeded: exiting...")
+		k.SetSaveSuccess(opts.Autosave)
+	} else {
+		log.Warningf("Save failed: exiting... %v", err)
+		k.SetSaveError(err)
+	}
+	if opts.Resume {
+		k.BeforeResume(ctx)
+	} else {
+		// Kill the sandbox.
+		k.Kill(linux.WaitStatusExit(0))
+	}
 	return err
 }
 
diff --git a/pkg/sentry/vfs/save_restore.go b/pkg/sentry/vfs/save_restore.go
index 5ceb4c36d..76f4687b9 100644
--- a/pkg/sentry/vfs/save_restore.go
+++ b/pkg/sentry/vfs/save_restore.go
@@ -54,6 +54,10 @@ type FilesystemImplSaveRestoreExtension interface {
 	// PrepareSave prepares this filesystem for serialization.
 	PrepareSave(ctx context.Context) error
 
+	// BeforeResume is called before the kernel is resumed after save. It can be
+	// used to clean up any state that should be discarded after save.
+	BeforeResume(ctx context.Context)
+
 	// CompleteRestore completes restoration from checkpoint for this
 	// filesystem after deserialization.
 	CompleteRestore(ctx context.Context, opts CompleteRestoreOptions) error
@@ -73,6 +77,17 @@ func (vfs *VirtualFilesystem) PrepareSave(ctx context.Context) error {
 	return nil
 }
 
+// BeforeResume is called before the kernel is resumed after save and allows
+// filesystems to clean up S/R state.
+func (vfs *VirtualFilesystem) BeforeResume(ctx context.Context) {
+	for fs := range vfs.getFilesystems() {
+		if ext, ok := fs.impl.(FilesystemImplSaveRestoreExtension); ok {
+			ext.BeforeResume(ctx)
+		}
+		fs.DecRef(ctx)
+	}
+}
+
 // CompleteRestore completes restoration from checkpoint for all filesystems
 // after deserialization.
 func (vfs *VirtualFilesystem) CompleteRestore(ctx context.Context, opts *CompleteRestoreOptions) error {
diff --git a/pkg/shim/BUILD b/pkg/shim/v1/BUILD
similarity index 90%
rename from pkg/shim/BUILD
rename to pkg/shim/v1/BUILD
index f09dbbad9..3628316e6 100644
--- a/pkg/shim/BUILD
+++ b/pkg/shim/v1/BUILD
@@ -6,13 +6,13 @@ package(
 )
 
 go_library(
-    name = "shim",
+    name = "v1",
     srcs = ["service.go"],
     visibility = ["//shim:__subpackages__"],
     deps = [
         "//pkg/cleanup",
-        "//pkg/shim/extension",
-        "//pkg/shim/runsc",
+        "//pkg/shim/v1/extension",
+        "//pkg/shim/v1/runsc",
         "//pkg/sync",
         "@com_github_containerd_containerd//namespaces:go_default_library",
         "@com_github_containerd_containerd//runtime/v2/shim:go_default_library",
diff --git a/pkg/shim/extension/BUILD b/pkg/shim/v1/extension/BUILD
similarity index 100%
rename from pkg/shim/extension/BUILD
rename to pkg/shim/v1/extension/BUILD
diff --git a/pkg/shim/extension/extension.go b/pkg/shim/v1/extension/extension.go
similarity index 100%
rename from pkg/shim/extension/extension.go
rename to pkg/shim/v1/extension/extension.go
diff --git a/pkg/shim/proc/BUILD b/pkg/shim/v1/proc/BUILD
similarity index 92%
rename from pkg/shim/proc/BUILD
rename to pkg/shim/v1/proc/BUILD
index c367657bc..e3bf35846 100644
--- a/pkg/shim/proc/BUILD
+++ b/pkg/shim/v1/proc/BUILD
@@ -25,9 +25,9 @@ go_library(
     deps = [
         "//pkg/atomicbitops",
         "//pkg/cleanup",
-        "//pkg/shim/extension",
-        "//pkg/shim/runsccmd",
-        "//pkg/shim/utils",
+        "//pkg/shim/v1/extension",
+        "//pkg/shim/v1/runsccmd",
+        "//pkg/shim/v1/utils",
         "@com_github_containerd_console//:go_default_library",
         "@com_github_containerd_containerd//mount:go_default_library",
         "@com_github_containerd_containerd//pkg/stdio:go_default_library",
diff --git a/pkg/shim/proc/deleted_state.go b/pkg/shim/v1/proc/deleted_state.go
similarity index 97%
rename from pkg/shim/proc/deleted_state.go
rename to pkg/shim/v1/proc/deleted_state.go
index 26b008dd5..cbde45148 100644
--- a/pkg/shim/proc/deleted_state.go
+++ b/pkg/shim/v1/proc/deleted_state.go
@@ -22,7 +22,7 @@ import (
 	"github.com/containerd/console"
 	"github.com/containerd/errdefs"
 	runc "github.com/containerd/go-runc"
-	"gvisor.dev/gvisor/pkg/shim/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
 )
 
 type deletedState struct{}
diff --git a/pkg/shim/proc/exec.go b/pkg/shim/v1/proc/exec.go
similarity index 98%
rename from pkg/shim/proc/exec.go
rename to pkg/shim/v1/proc/exec.go
index 6e7624415..6393cd791 100644
--- a/pkg/shim/proc/exec.go
+++ b/pkg/shim/v1/proc/exec.go
@@ -33,8 +33,8 @@ import (
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/pkg/cleanup"
-	"gvisor.dev/gvisor/pkg/shim/extension"
-	"gvisor.dev/gvisor/pkg/shim/runsccmd"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/runsccmd"
 )
 
 type execProcess struct {
diff --git a/pkg/shim/proc/exec_state.go b/pkg/shim/v1/proc/exec_state.go
similarity index 98%
rename from pkg/shim/proc/exec_state.go
rename to pkg/shim/v1/proc/exec_state.go
index d1c1d589f..35ac72462 100644
--- a/pkg/shim/proc/exec_state.go
+++ b/pkg/shim/v1/proc/exec_state.go
@@ -20,7 +20,7 @@ import (
 	"fmt"
 
 	"github.com/containerd/console"
-	"gvisor.dev/gvisor/pkg/shim/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
 )
 
 type execState interface {
diff --git a/pkg/shim/proc/init.go b/pkg/shim/v1/proc/init.go
similarity index 99%
rename from pkg/shim/proc/init.go
rename to pkg/shim/v1/proc/init.go
index d6c83a41a..1868286fd 100644
--- a/pkg/shim/proc/init.go
+++ b/pkg/shim/v1/proc/init.go
@@ -36,9 +36,9 @@ import (
 	runc "github.com/containerd/go-runc"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
 	"golang.org/x/sys/unix"
-	"gvisor.dev/gvisor/pkg/shim/extension"
-	"gvisor.dev/gvisor/pkg/shim/runsccmd"
-	"gvisor.dev/gvisor/pkg/shim/utils"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/runsccmd"
+	"gvisor.dev/gvisor/pkg/shim/v1/utils"
 )
 
 const statusStopped = "stopped"
diff --git a/pkg/shim/proc/init_state.go b/pkg/shim/v1/proc/init_state.go
similarity index 99%
rename from pkg/shim/proc/init_state.go
rename to pkg/shim/v1/proc/init_state.go
index c9894b370..d564f3a2e 100644
--- a/pkg/shim/proc/init_state.go
+++ b/pkg/shim/v1/proc/init_state.go
@@ -23,7 +23,7 @@ import (
 	runc "github.com/containerd/go-runc"
 	"golang.org/x/sys/unix"
 
-	"gvisor.dev/gvisor/pkg/shim/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
 )
 
 type stateTransition int
diff --git a/pkg/shim/proc/io.go b/pkg/shim/v1/proc/io.go
similarity index 100%
rename from pkg/shim/proc/io.go
rename to pkg/shim/v1/proc/io.go
diff --git a/pkg/shim/proc/proc.go b/pkg/shim/v1/proc/proc.go
similarity index 100%
rename from pkg/shim/proc/proc.go
rename to pkg/shim/v1/proc/proc.go
diff --git a/pkg/shim/proc/types.go b/pkg/shim/v1/proc/types.go
similarity index 100%
rename from pkg/shim/proc/types.go
rename to pkg/shim/v1/proc/types.go
diff --git a/pkg/shim/proc/utils.go b/pkg/shim/v1/proc/utils.go
similarity index 97%
rename from pkg/shim/proc/utils.go
rename to pkg/shim/v1/proc/utils.go
index 6b8f48d43..467d667c2 100644
--- a/pkg/shim/proc/utils.go
+++ b/pkg/shim/v1/proc/utils.go
@@ -22,7 +22,7 @@ import (
 	"strings"
 	"time"
 
-	"gvisor.dev/gvisor/pkg/shim/runsccmd"
+	"gvisor.dev/gvisor/pkg/shim/v1/runsccmd"
 )
 
 const (
diff --git a/pkg/shim/runsc/BUILD b/pkg/shim/v1/runsc/BUILD
similarity index 86%
rename from pkg/shim/runsc/BUILD
rename to pkg/shim/v1/runsc/BUILD
index 0207fc6f3..788bb4ca1 100644
--- a/pkg/shim/runsc/BUILD
+++ b/pkg/shim/v1/runsc/BUILD
@@ -20,17 +20,18 @@ go_library(
     visibility = ["//pkg/shim:__subpackages__"],
     deps = [
         "//pkg/cleanup",
-        "//pkg/shim/extension",
-        "//pkg/shim/proc",
-        "//pkg/shim/runsccmd",
-        "//pkg/shim/runtimeoptions",
-        "//pkg/shim/runtimeoptions/v14",
-        "//pkg/shim/utils",
+        "//pkg/shim/v1/extension",
+        "//pkg/shim/v1/proc",
+        "//pkg/shim/v1/runsccmd",
+        "//pkg/shim/v1/runtimeoptions",
+        "//pkg/shim/v1/runtimeoptions/v14",
+        "//pkg/shim/v1/utils",
         "//runsc/specutils",
         "@com_github_burntsushi_toml//:go_default_library",
         "@com_github_containerd_cgroups//:go_default_library",
         "@com_github_containerd_cgroups//stats/v1:go_default_library",
         "@com_github_containerd_cgroups//v2:go_default_library",
+        "@com_github_containerd_cgroups//v2/stats:go_default_library",
         "@com_github_containerd_console//:go_default_library",
         "@com_github_containerd_containerd//api/events:go_default_library",
         "@com_github_containerd_containerd//api/types/task:go_default_library",
@@ -46,6 +47,7 @@ go_library(
         "@com_github_containerd_containerd//sys/reaper:go_default_library",
         "@com_github_containerd_errdefs//:go_default_library",
         "@com_github_containerd_fifo//:go_default_library",
+        "@com_github_containerd_go_runc//:go_default_library",
         "@com_github_containerd_log//:go_default_library",
         "@com_github_containerd_typeurl//:go_default_library",
         "@com_github_gogo_protobuf//types:go_default_library",
@@ -60,7 +62,7 @@ go_test(
     srcs = ["service_test.go"],
     library = ":runsc",
     deps = [
-        "//pkg/shim/utils",
+        "//pkg/shim/v1/utils",
         "@com_github_opencontainers_runtime_spec//specs-go:go_default_library",
     ],
 )
diff --git a/pkg/shim/runsc/api.go b/pkg/shim/v1/runsc/api.go
similarity index 100%
rename from pkg/shim/runsc/api.go
rename to pkg/shim/v1/runsc/api.go
diff --git a/pkg/shim/runsc/debug.go b/pkg/shim/v1/runsc/debug.go
similarity index 100%
rename from pkg/shim/runsc/debug.go
rename to pkg/shim/v1/runsc/debug.go
diff --git a/pkg/shim/runsc/epoll.go b/pkg/shim/v1/runsc/epoll.go
similarity index 100%
rename from pkg/shim/runsc/epoll.go
rename to pkg/shim/v1/runsc/epoll.go
diff --git a/pkg/shim/runsc/oom_v2.go b/pkg/shim/v1/runsc/oom_v2.go
similarity index 100%
rename from pkg/shim/runsc/oom_v2.go
rename to pkg/shim/v1/runsc/oom_v2.go
diff --git a/pkg/shim/runsc/options.go b/pkg/shim/v1/runsc/options.go
similarity index 100%
rename from pkg/shim/runsc/options.go
rename to pkg/shim/v1/runsc/options.go
diff --git a/pkg/shim/runsc/service.go b/pkg/shim/v1/runsc/service.go
similarity index 92%
rename from pkg/shim/runsc/service.go
rename to pkg/shim/v1/runsc/service.go
index a9c1b2653..9bb73b477 100644
--- a/pkg/shim/runsc/service.go
+++ b/pkg/shim/v1/runsc/service.go
@@ -29,6 +29,7 @@ import (
 	"github.com/containerd/cgroups"
 	cgroupsstats "github.com/containerd/cgroups/stats/v1"
 	cgroupsv2 "github.com/containerd/cgroups/v2"
+	cgroupsv2stats "github.com/containerd/cgroups/v2/stats"
 	"github.com/containerd/console"
 	"github.com/containerd/containerd/api/events"
 	"github.com/containerd/containerd/api/types/task"
@@ -42,6 +43,7 @@ import (
 	taskAPI "github.com/containerd/containerd/runtime/v2/task"
 	"github.com/containerd/containerd/sys/reaper"
 	"github.com/containerd/errdefs"
+	runc "github.com/containerd/go-runc"
 	"github.com/containerd/log"
 	"github.com/containerd/typeurl"
 	"github.com/gogo/protobuf/types"
@@ -49,13 +51,13 @@ import (
 	"github.com/sirupsen/logrus"
 	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/pkg/cleanup"
-	"gvisor.dev/gvisor/pkg/shim/runtimeoptions/v14"
+	"gvisor.dev/gvisor/pkg/shim/v1/runtimeoptions/v14"
 
-	"gvisor.dev/gvisor/pkg/shim/extension"
-	"gvisor.dev/gvisor/pkg/shim/proc"
-	"gvisor.dev/gvisor/pkg/shim/runsccmd"
-	"gvisor.dev/gvisor/pkg/shim/runtimeoptions"
-	"gvisor.dev/gvisor/pkg/shim/utils"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/proc"
+	"gvisor.dev/gvisor/pkg/shim/v1/runsccmd"
+	"gvisor.dev/gvisor/pkg/shim/v1/runtimeoptions"
+	"gvisor.dev/gvisor/pkg/shim/v1/utils"
 	"gvisor.dev/gvisor/runsc/specutils"
 )
 
@@ -660,6 +662,18 @@ func (s *runscService) Stats(ctx context.Context, r *taskAPI.StatsRequest) (*tas
 	// as runc.
 	//
 	// [0]: https://github.com/google/gvisor/blob/277a0d5a1fbe8272d4729c01ee4c6e374d047ebc/runsc/boot/events.go#L61-L81
+	return s.getStats(stats, r)
+}
+
+func (s *runscService) getStats(stats *runc.Stats, r *taskAPI.StatsRequest) (*taskAPI.StatsResponse, error) {
+	if s.opts.RunscConfig["systemd-cgroup"] == "true" {
+		return s.getV2Stats(stats, r)
+	} else {
+		return s.getV1Stats(stats, r)
+	}
+}
+
+func (s *runscService) getV1Stats(stats *runc.Stats, r *taskAPI.StatsRequest) (*taskAPI.StatsResponse, error) {
 	metrics := &cgroupsstats.Metrics{
 		CPU: &cgroupsstats.CPUStat{
 			Usage: &cgroupsstats.CPUUsage{
@@ -708,10 +722,45 @@ func (s *runscService) Stats(ctx context.Context, r *taskAPI.StatsRequest) (*tas
 	}
 	data, err := typeurl.MarshalAny(metrics)
 	if err != nil {
-		log.L.Debugf("Stats error, id: %s: %v", r.ID, err)
+		log.L.Debugf("Stats error v1, id: %s: %v", r.ID, err)
 		return nil, err
 	}
-	log.L.Debugf("Stats success, id: %s: %+v", r.ID, data)
+	log.L.Debugf("Stats success v1, id: %s: %+v", r.ID, data)
+	return &taskAPI.StatsResponse{
+		Stats: data,
+	}, nil
+}
+
+func (s *runscService) getV2Stats(stats *runc.Stats, r *taskAPI.StatsRequest) (*taskAPI.StatsResponse, error) {
+	metrics := &cgroupsv2stats.Metrics{
+		// The CGroup V2 stats are in microseconds instead of nanoseconds so divide by 1000
+		CPU: &cgroupsv2stats.CPUStat{
+			UsageUsec:     stats.Cpu.Usage.Total / 1000,
+			UserUsec:      stats.Cpu.Usage.User / 1000,
+			SystemUsec:    stats.Cpu.Usage.Kernel / 1000,
+			NrPeriods:     stats.Cpu.Throttling.Periods,
+			NrThrottled:   stats.Cpu.Throttling.ThrottledPeriods,
+			ThrottledUsec: stats.Cpu.Throttling.ThrottledTime / 1000,
+		},
+		Memory: &cgroupsv2stats.MemoryStat{
+			Usage:      stats.Memory.Usage.Usage,
+			UsageLimit: stats.Memory.Usage.Limit,
+			SwapUsage:  stats.Memory.Swap.Usage,
+			SwapLimit:  stats.Memory.Swap.Limit,
+			Slab:       stats.Memory.Kernel.Usage,
+			File:       stats.Memory.Cache,
+		},
+		Pids: &cgroupsv2stats.PidsStat{
+			Current: stats.Pids.Current,
+			Limit:   stats.Pids.Limit,
+		},
+	}
+	data, err := typeurl.MarshalAny(metrics)
+	if err != nil {
+		log.L.Debugf("Stats error v2, id: %s: %v", r.ID, err)
+		return nil, err
+	}
+	log.L.Debugf("Stats success v2, id: %s: %+v", r.ID, data)
 	return &taskAPI.StatsResponse{
 		Stats: data,
 	}, nil
diff --git a/pkg/shim/runsc/service_linux.go b/pkg/shim/v1/runsc/service_linux.go
similarity index 100%
rename from pkg/shim/runsc/service_linux.go
rename to pkg/shim/v1/runsc/service_linux.go
diff --git a/pkg/shim/runsc/service_test.go b/pkg/shim/v1/runsc/service_test.go
similarity index 98%
rename from pkg/shim/runsc/service_test.go
rename to pkg/shim/v1/runsc/service_test.go
index 8c7464cf9..30543f37a 100644
--- a/pkg/shim/runsc/service_test.go
+++ b/pkg/shim/v1/runsc/service_test.go
@@ -18,7 +18,7 @@ import (
 	"testing"
 
 	specs "github.com/opencontainers/runtime-spec/specs-go"
-	"gvisor.dev/gvisor/pkg/shim/utils"
+	"gvisor.dev/gvisor/pkg/shim/v1/utils"
 )
 
 func TestCgroupPath(t *testing.T) {
diff --git a/pkg/shim/runsc/state.go b/pkg/shim/v1/runsc/state.go
similarity index 100%
rename from pkg/shim/runsc/state.go
rename to pkg/shim/v1/runsc/state.go
diff --git a/pkg/shim/runsccmd/BUILD b/pkg/shim/v1/runsccmd/BUILD
similarity index 100%
rename from pkg/shim/runsccmd/BUILD
rename to pkg/shim/v1/runsccmd/BUILD
diff --git a/pkg/shim/runsccmd/runsc.go b/pkg/shim/v1/runsccmd/runsc.go
similarity index 100%
rename from pkg/shim/runsccmd/runsc.go
rename to pkg/shim/v1/runsccmd/runsc.go
diff --git a/pkg/shim/runsccmd/utils.go b/pkg/shim/v1/runsccmd/utils.go
similarity index 100%
rename from pkg/shim/runsccmd/utils.go
rename to pkg/shim/v1/runsccmd/utils.go
diff --git a/pkg/shim/runtimeoptions/BUILD b/pkg/shim/v1/runtimeoptions/BUILD
similarity index 94%
rename from pkg/shim/runtimeoptions/BUILD
rename to pkg/shim/v1/runtimeoptions/BUILD
index 54f773ae7..7db78e7e3 100644
--- a/pkg/shim/runtimeoptions/BUILD
+++ b/pkg/shim/v1/runtimeoptions/BUILD
@@ -18,7 +18,7 @@ go_library(
         "runtimeoptions.go",
         "runtimeoptions_cri.go",
     ],
-    visibility = ["//pkg/shim/runsc:__pkg__"],
+    visibility = ["//pkg/shim/v1/runsc:__pkg__"],
     deps = ["@com_github_gogo_protobuf//proto:go_default_library"],
 )
 
diff --git a/pkg/shim/runtimeoptions/runtimeoptions.go b/pkg/shim/v1/runtimeoptions/runtimeoptions.go
similarity index 100%
rename from pkg/shim/runtimeoptions/runtimeoptions.go
rename to pkg/shim/v1/runtimeoptions/runtimeoptions.go
diff --git a/pkg/shim/runtimeoptions/runtimeoptions.proto b/pkg/shim/v1/runtimeoptions/runtimeoptions.proto
similarity index 100%
rename from pkg/shim/runtimeoptions/runtimeoptions.proto
rename to pkg/shim/v1/runtimeoptions/runtimeoptions.proto
diff --git a/pkg/shim/runtimeoptions/runtimeoptions_cri.go b/pkg/shim/v1/runtimeoptions/runtimeoptions_cri.go
similarity index 100%
rename from pkg/shim/runtimeoptions/runtimeoptions_cri.go
rename to pkg/shim/v1/runtimeoptions/runtimeoptions_cri.go
diff --git a/pkg/shim/runtimeoptions/runtimeoptions_test.go b/pkg/shim/v1/runtimeoptions/runtimeoptions_test.go
similarity index 100%
rename from pkg/shim/runtimeoptions/runtimeoptions_test.go
rename to pkg/shim/v1/runtimeoptions/runtimeoptions_test.go
diff --git a/pkg/shim/runtimeoptions/v14/BUILD b/pkg/shim/v1/runtimeoptions/v14/BUILD
similarity index 94%
rename from pkg/shim/runtimeoptions/v14/BUILD
rename to pkg/shim/v1/runtimeoptions/v14/BUILD
index a47376a2e..027720217 100644
--- a/pkg/shim/runtimeoptions/v14/BUILD
+++ b/pkg/shim/v1/runtimeoptions/v14/BUILD
@@ -18,7 +18,7 @@ go_library(
         "runtimeoptions.go",
         "runtimeoptions_cri.go",
     ],
-    visibility = ["//pkg/shim/runsc:__pkg__"],
+    visibility = ["//pkg/shim/v1/runsc:__pkg__"],
     deps = ["@com_github_gogo_protobuf//proto:go_default_library"],
 )
 
diff --git a/pkg/shim/runtimeoptions/v14/runtimeoptions.go b/pkg/shim/v1/runtimeoptions/v14/runtimeoptions.go
similarity index 100%
rename from pkg/shim/runtimeoptions/v14/runtimeoptions.go
rename to pkg/shim/v1/runtimeoptions/v14/runtimeoptions.go
diff --git a/pkg/shim/runtimeoptions/v14/runtimeoptions.proto b/pkg/shim/v1/runtimeoptions/v14/runtimeoptions.proto
similarity index 100%
rename from pkg/shim/runtimeoptions/v14/runtimeoptions.proto
rename to pkg/shim/v1/runtimeoptions/v14/runtimeoptions.proto
diff --git a/pkg/shim/runtimeoptions/v14/runtimeoptions_cri.go b/pkg/shim/v1/runtimeoptions/v14/runtimeoptions_cri.go
similarity index 100%
rename from pkg/shim/runtimeoptions/v14/runtimeoptions_cri.go
rename to pkg/shim/v1/runtimeoptions/v14/runtimeoptions_cri.go
diff --git a/pkg/shim/runtimeoptions/v14/runtimeoptions_test.go b/pkg/shim/v1/runtimeoptions/v14/runtimeoptions_test.go
similarity index 100%
rename from pkg/shim/runtimeoptions/v14/runtimeoptions_test.go
rename to pkg/shim/v1/runtimeoptions/v14/runtimeoptions_test.go
diff --git a/pkg/shim/service.go b/pkg/shim/v1/service.go
similarity index 98%
rename from pkg/shim/service.go
rename to pkg/shim/v1/service.go
index 74113b738..d06140697 100644
--- a/pkg/shim/service.go
+++ b/pkg/shim/v1/service.go
@@ -12,8 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// Package shim implements Containerd Shim v2 interface.
-package shim
+// Package v1 implements Containerd Shim v2 interface.
+package v1
 
 import (
 	"context"
@@ -31,8 +31,8 @@ import (
 	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/pkg/cleanup"
 
-	"gvisor.dev/gvisor/pkg/shim/extension"
-	"gvisor.dev/gvisor/pkg/shim/runsc"
+	"gvisor.dev/gvisor/pkg/shim/v1/extension"
+	"gvisor.dev/gvisor/pkg/shim/v1/runsc"
 	"gvisor.dev/gvisor/pkg/sync"
 )
 
diff --git a/pkg/shim/utils/BUILD b/pkg/shim/v1/utils/BUILD
similarity index 100%
rename from pkg/shim/utils/BUILD
rename to pkg/shim/v1/utils/BUILD
diff --git a/pkg/shim/utils/annotations.go b/pkg/shim/v1/utils/annotations.go
similarity index 100%
rename from pkg/shim/utils/annotations.go
rename to pkg/shim/v1/utils/annotations.go
diff --git a/pkg/shim/utils/utils.go b/pkg/shim/v1/utils/utils.go
similarity index 100%
rename from pkg/shim/utils/utils.go
rename to pkg/shim/v1/utils/utils.go
diff --git a/pkg/shim/utils/volumes.go b/pkg/shim/v1/utils/volumes.go
similarity index 100%
rename from pkg/shim/utils/volumes.go
rename to pkg/shim/v1/utils/volumes.go
diff --git a/pkg/shim/utils/volumes_test.go b/pkg/shim/v1/utils/volumes_test.go
similarity index 100%
rename from pkg/shim/utils/volumes_test.go
rename to pkg/shim/v1/utils/volumes_test.go
diff --git a/runsc/boot/autosave.go b/runsc/boot/autosave.go
index 87cfb463d..0b787796a 100644
--- a/runsc/boot/autosave.go
+++ b/runsc/boot/autosave.go
@@ -18,7 +18,6 @@ import (
 	"bytes"
 	"fmt"
 
-	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/fd"
 	"gvisor.dev/gvisor/pkg/log"
 	"gvisor.dev/gvisor/pkg/sentry/arch"
@@ -28,42 +27,19 @@ import (
 	"gvisor.dev/gvisor/pkg/sync"
 )
 
-func getSaveOpts(l *Loader, k *kernel.Kernel, isResume bool) state.SaveOpts {
-	t, _ := state.CPUTime()
-	log.Infof("Before save CPU usage: %s", t.String())
-	saveOpts := state.SaveOpts{
-		Key:    nil,
-		Resume: isResume,
-		Callback: func(err error) {
-			t1, _ := state.CPUTime()
-			log.Infof("Save CPU usage: %s", (t1 - t).String())
-			if err == nil {
-				log.Infof("Save succeeded: exiting...")
-				k.SetSaveSuccess(true)
-			} else {
-				log.Warningf("Save failed: exiting... %v", err)
-				k.SetSaveError(err)
-			}
-
-			if !isResume {
-				// Kill the sandbox.
-				k.Kill(linux.WaitStatusExit(0))
-			}
-		},
-	}
-	return saveOpts
-}
-
 func getTargetForSaveResume(l *Loader) func(k *kernel.Kernel) {
 	return func(k *kernel.Kernel) {
 		l.addVersionToCheckpoint()
 		l.addContainerSpecsToCheckpoint()
-		saveOpts := getSaveOpts(l, k, true /* isResume */)
 		// Store the state file contents in a buffer for save-resume.
 		// There is no need to verify the state file, we just need the
 		// sandbox to continue running after save.
 		var buf bytes.Buffer
-		saveOpts.Destination = &buf
+		saveOpts := state.SaveOpts{
+			Autosave:    true,
+			Resume:      true,
+			Destination: &buf,
+		}
 		saveOpts.Save(k.SupervisorContext(), k, l.watchdog)
 	}
 }
@@ -78,8 +54,11 @@ func getTargetForSaveRestore(l *Loader, files []*fd.FD) func(k *kernel.Kernel) {
 		once.Do(func() {
 			l.addVersionToCheckpoint()
 			l.addContainerSpecsToCheckpoint()
-			saveOpts := getSaveOpts(l, k, false /* isResume */)
-			saveOpts.Destination = files[0]
+			saveOpts := state.SaveOpts{
+				Autosave:    true,
+				Resume:      false,
+				Destination: files[0],
+			}
 			if len(files) == 3 {
 				saveOpts.PagesMetadata = files[1]
 				saveOpts.PagesFile = files[2]
diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go
index 4ae3b787e..0dbabcd20 100644
--- a/runsc/boot/loader.go
+++ b/runsc/boot/loader.go
@@ -208,9 +208,7 @@ type Loader struct {
 	// /sys/devices/virtual/dmi/id/product_name.
 	productName string
 
-	// hostShmemHuge is the host's value of
-	// /sys/kernel/mm/transparent_hugepage/shmem_enabled.
-	hostShmemHuge string
+	hostTHP HostTHP
 
 	// mu guards the fields below.
 	mu sync.Mutex
@@ -354,14 +352,23 @@ type Args struct {
 	// NvidiaDriverVersion is the NVIDIA driver ABI version to use for
 	// communicating with NVIDIA devices on the host.
 	NvidiaDriverVersion string
-	// HostShmemHuge is the host's value of
-	// /sys/kernel/mm/transparent_hugepage/shmem_enabled, or empty if this is
-	// unknown.
-	HostShmemHuge string
+	// HostTHP contains host transparent hugepage settings.
+	HostTHP HostTHP
 
 	SaveFDs []*fd.FD
 }
 
+// HostTHP holds host transparent hugepage settings.
+type HostTHP struct {
+	// ShmemEnabled is the selected option in
+	// /sys/kernel/mm/transparent_hugepage/shmem_enabled.
+	ShmemEnabled string
+
+	// Defrag is the selected option in
+	// /sys/kernel/mm/transparent_hugepage/defrag.
+	Defrag string
+}
+
 const (
 	// startingStdioFD is the starting stdioFD number used during sandbox
 	// start and restore. This makes sure the stdioFDs are always the same
@@ -439,7 +446,7 @@ func New(args Args) (*Loader, error) {
 		sharedMounts:   make(map[string]*vfs.Mount),
 		stopProfiling:  stopProfiling,
 		productName:    args.ProductName,
-		hostShmemHuge:  args.HostShmemHuge,
+		hostTHP:        args.HostTHP,
 		containerIDs:   make(map[string]string),
 		containerSpecs: make(map[string]*specs.Spec),
 		saveFDs:        args.SaveFDs,
@@ -508,7 +515,7 @@ func New(args Args) (*Loader, error) {
 	l.k = &kernel.Kernel{Platform: p}
 
 	// Create memory file.
-	mf, err := createMemoryFile(args.Conf.AppHugePages, args.HostShmemHuge)
+	mf, err := createMemoryFile(args.Conf.AppHugePages, args.HostTHP)
 	if err != nil {
 		return nil, fmt.Errorf("creating memory file: %w", err)
 	}
@@ -787,7 +794,7 @@ func createPlatform(conf *config.Config, deviceFile *fd.FD) (platform.Platform,
 	return p.New(deviceFile)
 }
 
-func createMemoryFile(appHugePages bool, hostShmemHuge string) (*pgalloc.MemoryFile, error) {
+func createMemoryFile(appHugePages bool, hostTHP HostTHP) (*pgalloc.MemoryFile, error) {
 	const memfileName = "runsc-memory"
 	memfd, err := memutil.CreateMemFD(memfileName, 0)
 	if err != nil {
@@ -801,27 +808,45 @@ func createMemoryFile(appHugePages bool, hostShmemHuge string) (*pgalloc.MemoryF
 		// in a mount namespace in which the relevant cgroupfs is not visible.
 	}
 	if appHugePages {
-		switch hostShmemHuge {
+		switch hostTHP.ShmemEnabled {
 		case "":
-			log.Infof("Disabling application huge pages: host shmem_huge is unknown")
+			log.Infof("Disabling application huge pages: host shmem_enabled is unknown")
 		case "never", "deny":
-			log.Infof("Disabling application huge pages: host shmem_huge is %q", hostShmemHuge)
+			log.Infof("Disabling application huge pages: host shmem_enabled is %q", hostTHP.ShmemEnabled)
 		case "advise":
-			log.Infof("Enabling application huge pages: host shmem_huge is %q", hostShmemHuge)
-			mfopts.ExpectHugepages = true
-			mfopts.AdviseHugepage = true
+			switch hostTHP.Defrag {
+			case "":
+				log.Infof("Disabling application huge pages: host shmem_enabled is %q, host defrag is unknown", hostTHP.ShmemEnabled)
+			case "always", "defer", "never":
+				// Allocations on MADV_HUGEPAGE pages will invoke direct
+				// compaction ("always"), wake kcompactd ("defer"), or do
+				// neither ("never"), consistent with host private anonymous
+				// memory mappings, so using MADV_HUGEPAGE shouldn't cause a
+				// regression vs. running natively.
+				log.Infof("Enabling application huge pages: host shmem_enabled is %q, host defrag is %q", hostTHP.ShmemEnabled, hostTHP.Defrag)
+				mfopts.ExpectHugepages = true
+				mfopts.AdviseHugepage = true
+			case "defer+madvise", "madvise":
+				// Allocations on MADV_HUGEPAGE pages may invoke direct
+				// compaction whereas allocations on host private anonymous
+				// memory mappings will not, so using MADV_HUGEPAGE may degrade
+				// performance.
+				log.Infof("Disabling application huge pages: host shmem_enabled is %q, host defrag is %q", hostTHP.ShmemEnabled, hostTHP.Defrag)
+			default:
+				log.Warningf("Disabling application huge pages: host shmem_enabled is %q, host defrag is unknown value %q", hostTHP.ShmemEnabled, hostTHP.Defrag)
+			}
 		case "always", "within_size":
-			log.Infof("Enabling application huge pages: host shmem_huge is %q", hostShmemHuge)
+			log.Infof("Enabling application huge pages: host shmem_enabled is %q", hostTHP.ShmemEnabled)
 			// In these cases, memfds will default to using huge pages, and we have to
 			// explicitly ask for small pages.
 			mfopts.ExpectHugepages = true
 			mfopts.AdviseNoHugepage = true
 		case "force":
-			log.Infof("Enabling application huge pages: host shmem_huge is %q", hostShmemHuge)
+			log.Infof("Enabling application huge pages: host shmem_enabled is %q", hostTHP.ShmemEnabled)
 			// The kernel will ignore MADV_NOHUGEPAGE, so don't bother.
 			mfopts.ExpectHugepages = true
 		default:
-			log.Infof("Disabling application huge pages: host shmem_huge is unknown value %q", hostShmemHuge)
+			log.Warningf("Disabling application huge pages: host shmem_enabled is unknown value %q", hostTHP.ShmemEnabled)
 		}
 	}
 
diff --git a/runsc/boot/restore.go b/runsc/boot/restore.go
index f1e1fa0de..9ebb1603d 100644
--- a/runsc/boot/restore.go
+++ b/runsc/boot/restore.go
@@ -171,7 +171,7 @@ func (r *restorer) restore(l *Loader) error {
 		Platform: p,
 	}
 
-	mf, err := createMemoryFile(l.root.conf.AppHugePages, l.hostShmemHuge)
+	mf, err := createMemoryFile(l.root.conf.AppHugePages, l.hostTHP)
 	if err != nil {
 		return fmt.Errorf("creating memory file: %v", err)
 	}
diff --git a/runsc/cmd/boot.go b/runsc/cmd/boot.go
index b18c12baa..2b78c6606 100644
--- a/runsc/cmd/boot.go
+++ b/runsc/cmd/boot.go
@@ -159,8 +159,7 @@ type Boot struct {
 	// /sys/devices/virtual/dmi/id/product_name.
 	productName string
 
-	// Value of /sys/kernel/mm/transparent_hugepage/shmem_enabled on the host.
-	hostShmemHuge string
+	hostTHP boot.HostTHP
 
 	// FDs for profile data.
 	profileFDs profile.FDArgs
@@ -217,7 +216,8 @@ func (b *Boot) SetFlags(f *flag.FlagSet) {
 	f.BoolVar(&b.attached, "attached", false, "if attached is true, kills the sandbox process when the parent process terminates")
 	f.StringVar(&b.productName, "product-name", "", "value to show in /sys/devices/virtual/dmi/id/product_name")
 	f.StringVar(&b.nvidiaDriverVersion, "nvidia-driver-version", "", "Nvidia driver version on the host")
-	f.StringVar(&b.hostShmemHuge, "host-shmem-huge", "", "value of /sys/kernel/mm/transparent_hugepage/shmem_enabled on the host")
+	f.StringVar(&b.hostTHP.ShmemEnabled, "host-thp-shmem-enabled", "", "value of /sys/kernel/mm/transparent_hugepage/shmem_enabled on the host")
+	f.StringVar(&b.hostTHP.Defrag, "host-thp-defrag", "", "value of /sys/kernel/mm/transparent_hugepage/defrag on the host")
 
 	// Open FDs that are donated to the sandbox.
 	f.IntVar(&b.specFD, "spec-fd", -1, "required fd with the container spec")
@@ -275,14 +275,26 @@ func (b *Boot) Execute(_ context.Context, f *flag.FlagSet, args ...any) subcomma
 			argOverride["product-name"] = b.productName
 		}
 	}
-	if conf.AppHugePages && len(b.hostShmemHuge) == 0 {
-		hostShmemHuge, err := hostmm.GetTransparentHugepageEnum("shmem_enabled")
-		if err != nil {
-			log.Warningf("Failed to infer --host-shmem-huge: %v", err)
-		} else {
-			b.hostShmemHuge = hostShmemHuge
-			log.Infof("Setting host-shmem-huge: %q", b.hostShmemHuge)
-			argOverride["host-shmem-huge"] = b.hostShmemHuge
+	if conf.AppHugePages {
+		if len(b.hostTHP.ShmemEnabled) == 0 {
+			val, err := hostmm.ReadTransparentHugepageEnum("shmem_enabled")
+			if err != nil {
+				log.Warningf("Failed to infer --host-thp-shmem-enabled: %v", err)
+			} else {
+				b.hostTHP.ShmemEnabled = val
+				log.Infof("Setting host-thp-shmem-enabled: %q", b.hostTHP.ShmemEnabled)
+				argOverride["host-thp-shmem-enabled"] = b.hostTHP.ShmemEnabled
+			}
+		}
+		if len(b.hostTHP.Defrag) == 0 {
+			val, err := hostmm.ReadTransparentHugepageEnum("defrag")
+			if err != nil {
+				log.Warningf("Failed to infer --host-thp-defrag", err)
+			} else {
+				b.hostTHP.Defrag = val
+				log.Infof("Setting host-thp-defrag: %q", b.hostTHP.Defrag)
+				argOverride["host-thp-defrag"] = b.hostTHP.Defrag
+			}
 		}
 	}
 
@@ -504,7 +516,7 @@ func (b *Boot) Execute(_ context.Context, f *flag.FlagSet, args ...any) subcomma
 		SinkFDs:             b.sinkFDs.GetArray(),
 		ProfileOpts:         b.profileFDs.ToOpts(),
 		NvidiaDriverVersion: b.nvidiaDriverVersion,
-		HostShmemHuge:       b.hostShmemHuge,
+		HostTHP:             b.hostTHP,
 		SaveFDs:             b.saveFDs.GetFDs(),
 	}
 	l, err := boot.New(bootArgs)
diff --git a/runsc/hostsettings/BUILD b/runsc/hostsettings/BUILD
index a0a4fbdd0..a98292e33 100644
--- a/runsc/hostsettings/BUILD
+++ b/runsc/hostsettings/BUILD
@@ -13,6 +13,7 @@ go_library(
     visibility = ["//:sandbox"],
     deps = [
         "//pkg/log",
+        "//pkg/sentry/hostmm",
         "//runsc/config",
     ],
 )
diff --git a/runsc/hostsettings/hostsettings.go b/runsc/hostsettings/hostsettings.go
index c2162553c..262380cc1 100644
--- a/runsc/hostsettings/hostsettings.go
+++ b/runsc/hostsettings/hostsettings.go
@@ -23,6 +23,7 @@ import (
 	"strings"
 
 	"gvisor.dev/gvisor/pkg/log"
+	"gvisor.dev/gvisor/pkg/sentry/hostmm"
 	"gvisor.dev/gvisor/runsc/config"
 )
 
@@ -189,12 +190,48 @@ func check(conf *config.Config) ([]*Delta, []error) {
 			path:    "/sys/kernel/mm/transparent_hugepage/shmem_enabled",
 			purpose: "turning on transparent hugepages support in shmem increases memory allocation performance",
 			delta: func(conf *config.Config, current string) (string, bool, error) {
-				// /sys/kernel/mm/transparent_hugepage/shmem_enabled is formatted like:
-				// `always within_size advise [never] deny force`.
-				if strings.Contains(current, "[always]") || strings.Contains(current, "[advise]") || strings.Contains(current, "[force]") || strings.Contains(current, "[within_size]") {
+				cur, err := hostmm.GetTransparentHugepageEnum(current)
+				if err != nil {
+					return "", false, err
+				}
+				switch cur {
+				case "always", "advise", "force", "within_size":
+					return "", false, nil
+				case "never":
+					return "advise", false, nil
+				case "deny":
+					// This is a non-default setting, so assume that it's
+					// admin-intended and don't try to change it.
+					return "", false, nil
+				default:
+					// Linux can reasonably add new options, so this shouldn't
+					// be fatal.
+					log.Warningf("Unknown value for /sys/kernel/mm/transparent_hugepage/shmem_enabled: %s", cur)
+					return "", false, nil
+				}
+			},
+		},
+		{
+			path:    "/sys/kernel/mm/transparent_hugepage/defrag",
+			purpose: "disabling direct compaction improves page fault latency when hugepages are not immediately available",
+			delta: func(conf *config.Config, current string) (string, bool, error) {
+				cur, err := hostmm.GetTransparentHugepageEnum(current)
+				if err != nil {
+					return "", false, err
+				}
+				switch cur {
+				case "always", "defer", "never":
+					return "", false, nil
+				case "defer+madvise":
+					return "defer", false, nil
+				case "madvise":
+					return "never", false, nil
+				default:
+					// Linux can reasonably add new options, so this shouldn't
+					// be fatal.
+					log.Warningf("Unknown value for /sys/kernel/mm/transparent_hugepage/defrag: %s", cur)
 					return "", false, nil
 				}
-				return "advise", false, nil
 			},
 		},
 		{
diff --git a/shim/BUILD b/shim/BUILD
index c5b30adce..67d56dfa4 100644
--- a/shim/BUILD
+++ b/shim/BUILD
@@ -13,7 +13,7 @@ go_binary(
     visibility = [
         "//visibility:public",
     ],
-    deps = ["//shim/cli"],
+    deps = ["//shim/v1/cli"],
 )
 
 pkg_tar(
diff --git a/shim/main.go b/shim/main.go
index b87a20d08..6e258889c 100644
--- a/shim/main.go
+++ b/shim/main.go
@@ -16,7 +16,7 @@
 package main
 
 import (
-	"gvisor.dev/gvisor/shim/cli"
+	"gvisor.dev/gvisor/shim/v1/cli"
 )
 
 func main() {
diff --git a/shim/cli/BUILD b/shim/v1/cli/BUILD
similarity index 93%
rename from shim/cli/BUILD
rename to shim/v1/cli/BUILD
index 4eb42f319..715341144 100644
--- a/shim/cli/BUILD
+++ b/shim/v1/cli/BUILD
@@ -13,7 +13,7 @@ go_library(
         "//shim:__pkg__",
     ],
     deps = [
-        "//pkg/shim",
+        "//pkg/shim/v1",
         "@com_github_containerd_containerd//runtime/v2/shim:go_default_library",
     ],
 )
diff --git a/shim/cli/cli.go b/shim/v1/cli/cli.go
similarity index 95%
rename from shim/cli/cli.go
rename to shim/v1/cli/cli.go
index 068976c79..5fe24bd34 100644
--- a/shim/cli/cli.go
+++ b/shim/v1/cli/cli.go
@@ -19,7 +19,7 @@ package cli
 import (
 	containerdshim "github.com/containerd/containerd/runtime/v2/shim"
 
-	"gvisor.dev/gvisor/pkg/shim"
+	shim "gvisor.dev/gvisor/pkg/shim/v1"
 )
 
 // Main is the main entrypoint.
diff --git a/test/syscalls/linux/proc.cc b/test/syscalls/linux/proc.cc
index f9d4e1e6f..ba32717c9 100644
--- a/test/syscalls/linux/proc.cc
+++ b/test/syscalls/linux/proc.cc
@@ -424,6 +424,12 @@ void RemoveUnstableCPUInfoFields(std::vector<std::string>& cpu_info_fields) {
   }
 }
 
+TEST(ProcTest, RootInodeNumber) {
+  struct stat s;
+  ASSERT_THAT(stat("/proc", &s), SyscallSucceeds());
+  EXPECT_EQ(s.st_ino, 1);
+}
+
 TEST(ProcTest, NotFoundInRoot) {
   struct stat s;
   EXPECT_THAT(stat("/proc/foobar", &s), SyscallFailsWithErrno(ENOENT));