diff --git a/internlm/core/parallel/comm/__init__.py b/internlm/core/parallel/comm/__init__.py
index e69de29bb..be170f286 100644
--- a/internlm/core/parallel/comm/__init__.py
+++ b/internlm/core/parallel/comm/__init__.py
@@ -0,0 +1,3 @@
+from .attn_offload import get_offload_manager, initialize_offload_manager
+
+__all__ = ["initialize_offload_manager", "get_offload_manager"]
diff --git a/internlm/core/parallel/comm/attn_offload.py b/internlm/core/parallel/comm/attn_offload.py
new file mode 100644
index 000000000..da23f3ae8
--- /dev/null
+++ b/internlm/core/parallel/comm/attn_offload.py
@@ -0,0 +1,127 @@
+import torch
+
+from internlm.utils.common import get_current_device
+
+global_attn_offload = None
+
+
+class AttnOffloadManager:
+    """
+    A manager for attention output CPU offloading and GPU prefetch loading.
+    """
+
+    def __init__(self, enable_cpu_offload: bool = False) -> None:
+        # cpu offload overlapping
+        self.cpu_offload = enable_cpu_offload
+        # layer id mapping to flash attn output
+        self.fa_output_mapping = {}
+        self.fa_stream = torch.cuda.Stream()
+        self.d2h_final_event = torch.cuda.Event()
+        self.h2d_final_event = torch.cuda.Event()
+        # prepare for tensor buffer
+        self.tensor_id_to_tensor_bufs = {}
+
+    def get_tensor_buf_for_offloaded_tensor(self, tensor, layer_id, tensor_id):
+        """Get tensor buffer for offloaded tensor."""
+        layer_id = layer_id % 2
+        if layer_id not in self.tensor_id_to_tensor_bufs:
+            self.tensor_id_to_tensor_bufs[layer_id] = {}
+
+        if tensor_id not in self.tensor_id_to_tensor_bufs[layer_id]:
+            allocate_new_buf = True
+        else:
+            tensor_buf = self.tensor_id_to_tensor_bufs[layer_id][tensor_id]
+            allocate_new_buf = tensor_buf.size() == tensor.size() and tensor_buf.dtype == tensor.dtype
+
+        if allocate_new_buf:
+            # supposed to only execute once
+            buffer = torch.empty(
+                tensor.size(),
+                dtype=tensor.dtype,
+                layout=tensor.layout,
+                device=tensor.device,
+            )
+
+            self.tensor_id_to_tensor_bufs[layer_id][tensor_id] = buffer
+
+        return self.tensor_id_to_tensor_bufs[layer_id][tensor_id]
+
+    def insert_fa_output_with_layer(self, layer_idx, output):
+        assert layer_idx not in self.fa_output_mapping
+        if self.cpu_offload is False:
+            self.fa_output_mapping[layer_idx] = output
+            return
+
+        tensors = []
+        for tensor_id, tensor in enumerate(output):
+            if tensor is None:
+                tensors.append(None)
+                continue
+            tensor_buf = self.get_tensor_buf_for_offloaded_tensor(tensor, layer_idx, tensor_id)
+            tensor_buf.copy_(tensor)
+            tensors.append(tensor_buf)
+        self.fa_output_mapping[layer_idx] = tensors
+
+    def get_fa_output_with_layer(self, layer_idx):
+        assert layer_idx in self.fa_output_mapping
+        return self.fa_output_mapping.pop(layer_idx)
+
+    def offload_fa_output_with_layer(self, layer_idx):
+        assert layer_idx in self.fa_output_mapping
+
+        self.fa_stream.wait_stream(torch.cuda.current_stream())
+        self.fa_stream.wait_event(self.d2h_final_event)
+
+        with torch.cuda.stream(self.fa_stream):
+            _gpu_tensors = self.fa_output_mapping.pop(layer_idx)
+            _cpu_tensors = []
+            for _tensor in _gpu_tensors:
+                if _tensor is None:
+                    _cpu_tensors.append(_tensor)
+                    continue
+
+                _cpu_backup = torch.empty(
+                    _tensor.size(),
+                    dtype=_tensor.dtype,
+                    layout=_tensor.layout,
+                    device="cpu",
+                    pin_memory=True,
+                )
+                _cpu_backup.copy_(_tensor, non_blocking=True)
+                _cpu_tensors.append(_cpu_backup)
+
+                # _cpu_tensors.append(_tensor.to("cpu", non_blocking=False))
+
+            self.fa_output_mapping[layer_idx] = _cpu_tensors
+
+        self.fa_stream.record_event(self.d2h_final_event)
+
+    def preload_fa_output_with_layer(self, layer_idx):
+        assert layer_idx in self.fa_output_mapping
+
+        self.fa_stream.wait_stream(torch.cuda.current_stream())
+        self.fa_stream.wait_event(self.h2d_final_event)
+
+        # Important: get device before with stream, in stream get device is error
+        _device = get_current_device()
+        with torch.cuda.stream(self.fa_stream):
+            _cpu_tensors = self.fa_output_mapping.pop(layer_idx)
+            self.fa_output_mapping[layer_idx] = [
+                _tensor.to(device=_device, non_blocking=True) if _tensor is not None else _tensor
+                for _tensor in _cpu_tensors
+            ]
+
+        self.fa_stream.record_event(self.h2d_final_event)
+
+
+def initialize_offload_manager(enable_cpu_offload: bool = False):
+    global global_attn_offload
+    if global_attn_offload is None:
+        global_attn_offload = AttnOffloadManager(enable_cpu_offload)
+
+    return global_attn_offload
+
+
+def get_offload_manager():
+    assert global_attn_offload is not None
+    return global_attn_offload
diff --git a/internlm/core/parallel/comm/isp.py b/internlm/core/parallel/comm/isp.py
index 7e722c2fe..24677c090 100644
--- a/internlm/core/parallel/comm/isp.py
+++ b/internlm/core/parallel/comm/isp.py
@@ -37,6 +37,8 @@
     params_dispatch_with_condition,
 )
 
+from .attn_offload import get_offload_manager
+
 
 # not really useful, only for code hint.
 class WPCommunicator(ABC):
@@ -306,6 +308,7 @@ def __init__(
         overlap: bool = False,
         process_group: dist.ProcessGroup = None,
         is_moe: bool = False,
+        selective_ckpt_offload: bool = False,
     ) -> None:
         self.process_group = process_group
         self.overlap = overlap
@@ -316,6 +319,14 @@ def __init__(
         self._forward_prefetch_prerequisites = []
         self._forward_overlap_per = self._get_forward_overlap_granularity()
         self._launch_before_module = self._get_launch_before_module()
+        # As an optimization, do not release weight after forward for the last
+        # transformer block since wp would prefetch it immediately
+        self.layers_wp_not_release = []  # [gpc.config.isp_num_layers - 1]
+        self.layers_fa_not_release = [
+            gpc.config.isp_num_layers - 1,
+            int(gpc.config.model.checkpoint * gpc.config.isp_num_layers) - 1,
+        ]
+        self.sc_offload = selective_ckpt_offload
 
         # real overlap state for each chunk.
         self._overlap_states: Dict[int, ISPOverlapState] = {}
@@ -411,6 +422,7 @@ def is_allgather_launch_module(name, module):
                             self._overlap_states[cid].index_to_isp_modules[idx].append(child)
 
                             setattr(child, "isp_name", name)
+                            setattr(child, "isp_layer_idx", idx)
 
                             full_name = f"{cid}.{idx}.{name}"
                             setattr(
@@ -506,6 +518,25 @@ def _pre_forward_hook_for_prefetch_launch_module(self, module: nn.Module, *args)
                 if block_index + 1 < self._num_blocks:
                     self._all_gather_block_weight(block_index + 1)
 
+        # register offload and prefetch hook for selective ckpt with wo linear
+        if self.sc_offload is True:
+            # move current layer's attn output from GPU to CPU asynchronizely
+            if (
+                self.is_forward is True
+                and gpc.config.selective_checkpoint
+                and block_index not in self.layers_fa_not_release
+                and block_index < self._ckpt_block_num
+            ):
+                get_offload_manager().offload_fa_output_with_layer(layer_idx=block_index)
+
+            # load previous layer's attn output from CPU to GPU asynchronizely
+            if (
+                self.is_forward is False
+                and gpc.config.selective_checkpoint
+                and (0 <= (block_index - 1) < self._ckpt_block_num)
+            ):
+                get_offload_manager().preload_fa_output_with_layer(layer_idx=block_index - 1)
+
     def _pre_forward_hook_for_module(self, module: nn.Module, *args):  # pylint: disable=W0613
         if module not in self._weight_global_handle:
             self._all_gather_module_weight(module)
@@ -539,6 +570,9 @@ def _pre_forward_hook_for_module(self, module: nn.Module, *args):  # pylint: dis
                         self._all_gather_module_weight(next_module)
 
     def _post_forward_hook_for_module(self, module: nn.Module, *args):  # pylint: disable=W0613
+        if int(module.isp_layer_idx) in self.layers_wp_not_release:
+            # print(f"the layer {module.isp_layer_idx} after forward not clear weight")
+            return
         if not ((self._module_to_index[module] < self._ckpt_block_num) and self.is_forward is False):
             self._clear_handle(module)
             self._clear_weight(module)
diff --git a/internlm/core/trainer_builder.py b/internlm/core/trainer_builder.py
index d0ef284d4..cb45be728 100644
--- a/internlm/core/trainer_builder.py
+++ b/internlm/core/trainer_builder.py
@@ -11,6 +11,7 @@
 from internlm.checkpoint.checkpoint_manager import CheckpointManager
 from internlm.core.context import global_context as gpc
 from internlm.core.context.process_group_initializer import ParallelMode
+from internlm.core.parallel.comm import initialize_offload_manager
 from internlm.core.trainer import Trainer
 from internlm.data.streaming.utils import streaming_simple_resume
 from internlm.data.train_state import get_train_state
@@ -118,6 +119,9 @@ def __init__(
         # initialize isp communicator
         isp_communicator = initialize_parallel_communicator(model)
 
+        # initialize cpu offload manager for selective checkpoint
+        initialize_offload_manager(gpc.config.get("selective_checkpoint_offload", False))
+
         # initialize train state
         train_state = get_train_state(train_dl)
 
diff --git a/internlm/initialize/launch.py b/internlm/initialize/launch.py
index 35b3d646c..580ba0069 100644
--- a/internlm/initialize/launch.py
+++ b/internlm/initialize/launch.py
@@ -66,6 +66,8 @@ def get_default_parser():
 def args_sanity_check():
     assert gpc.config is not None, "config is not load!"
 
+    gpc.is_forward = True
+
     if "JOB_NAME" not in gpc.config:
         gpc.config._add_item("JOB_NAME", "AnonymousJob")
 
@@ -73,6 +75,13 @@ def args_sanity_check():
     if "model_type" not in gpc.config:
         gpc.config._add_item("model_type", ModelType.INTERNLM.name)
 
+    if gpc.config.model_type == "InternLM3_M":
+        # TODO: need check for isp overlap
+        num_layers = gpc.config.model.num_self_decoder_layers + gpc.config.model.num_cross_decoder_layers
+    else:
+        num_layers = gpc.config.model.num_layers
+    gpc.config.isp_num_layers = num_layers
+
     if "use_apex_adam" not in gpc.config:
         gpc.config._add_item("use_apex_adam", False)
 
@@ -399,17 +408,18 @@ def args_sanity_check():
         gpc.config.parallel["tensor"] = dict(size=gpc.config.parallel["tensor"], mode=TensorParallelMode.mtp.name)
     if gpc.config.parallel["tensor"].get("mode", None) is None:
         gpc.config.parallel["tensor"]["mode"] = TensorParallelMode.mtp.name
-    assert (
-        gpc.config.VOCAB_SIZE % gpc.config.parallel.tensor.size == 0
-    ), "VOCAB_SIZE must be integer multiple of tensor parallel size"
     if gpc.config.parallel["tensor"]["mode"] == TensorParallelMode.isp.name:
         assert not gpc.config.parallel.zero1.fsdp, "FSDP does not support isp"
         assert (
             torch.__version__ >= "2.1.0"
         ), f"requires torch>=2.1.0 when using isp but current version is {torch.__version__}"
-        assert (
-            gpc.config.VOCAB_SIZE % gpc.config.parallel.weight.size == 0
-        ), "VOCAB_SIZE must be integer multiple of wp size"
+
+    assert (
+        gpc.config.model.vocab_size % gpc.config.parallel.weight.size == 0
+    ), "model.vocab_size must be integer multiple of weight parallel size"
+    assert (
+        gpc.config.model.vocab_size % gpc.config.parallel.tensor.size == 0
+    ), "model.vocab_size must be integer multiple of tensor parallel size"
 
     assert gpc.config.parallel["tensor"].get("mode", None) in [
         TensorParallelMode.mtp.name,
@@ -532,7 +542,20 @@ def args_sanity_check():
         gpc.config.loss._add_item("moe_loss_coeff", 1.0)
 
     if "selective_checkpoint" not in gpc.config:
-        gpc.config._add_item("selective_checkpoint", False)
+        gpc.config.selective_checkpoint = False
+    if "selective_checkpoint_offload" not in gpc.config:
+        gpc.config.selective_checkpoint_offload = False
+    if gpc.config.selective_checkpoint is True:
+        assert (
+            gpc.config.parallel["tensor"]["mode"] == "isp"
+        ), "When using selective_checkpoint, tensor parallel mode must be isp"
+    if gpc.config.selective_checkpoint_offload is True:
+        assert (
+            gpc.config.selective_checkpoint is True
+        ), "When using selective_checkpoint_offload, selective_checkpoint must be True"
+        assert (
+            gpc.config.parallel.weight.launch_allgather_before == "wo"
+        ), "When using selective_checkpoint_offload, wp launch allgather communication should be set before 'wo' module"
 
     # moe not support overlap and zero1.5 for now
     if gpc.config.model.get("num_experts", 1) > 1:
diff --git a/internlm/model/ops/_flash_attn.py b/internlm/model/ops/_flash_attn.py
new file mode 100644
index 000000000..87aac2eb8
--- /dev/null
+++ b/internlm/model/ops/_flash_attn.py
@@ -0,0 +1,331 @@
+# Copyright (c) InternLM. All rights reserved.
+import torch
+
+from internlm.accelerator import get_accelerator
+from internlm.core.context import global_context as gpc
+from internlm.core.parallel.comm import get_offload_manager
+
+try:
+    import flash_attn
+    from flash_attn.flash_attn_interface import (
+        _flash_attn_varlen_backward,
+        _flash_attn_varlen_forward,
+    )
+
+    gpu_flash_attn_impl = True
+except (ModuleNotFoundError, ImportError):
+    gpu_flash_attn_impl = False
+
+internlm_accelerator = get_accelerator()
+device_backend = internlm_accelerator.get_accelerator_backend()
+
+
+class FlashAttnVarlenKVPackedFunc_V263(torch.autograd.Function):
+    """
+    Varlen KVPacked Func from Flash Attn v2.6.3.
+    """
+
+    @staticmethod
+    def forward(
+        ctx,
+        q,
+        kv,
+        cu_seqlens_q,
+        cu_seqlens_k,
+        max_seqlen_q,
+        max_seqlen_k,
+        dropout_p,
+        softmax_scale,
+        causal,
+        window_size,
+        softcap,
+        alibi_slopes,
+        deterministic,
+        return_softmax,
+        layer_idx,
+    ):
+        if softmax_scale is None:
+            softmax_scale = q.shape[-1] ** (-0.5)
+
+        k, v = kv[:, 0], kv[:, 1]
+
+        _ckpt_block_num = int(gpc.config.model.checkpoint * gpc.config.isp_num_layers)
+
+        if gpc.is_forward is False and gpc.config.selective_checkpoint and layer_idx < _ckpt_block_num:
+            out, out_padded, softmax_lse, S_dmask, rng_state = get_offload_manager().get_fa_output_with_layer(layer_idx)
+        else:
+            (
+                out,
+                q,
+                k,
+                v,
+                out_padded,
+                softmax_lse,
+                S_dmask,
+                rng_state,
+            ) = _flash_attn_varlen_forward(  # pylint: disable=E1123
+                q,
+                k,
+                v,
+                cu_seqlens_q,
+                cu_seqlens_k,
+                max_seqlen_q,
+                max_seqlen_k,
+                dropout_p,
+                softmax_scale,
+                causal=causal,
+                window_size=window_size,
+                softcap=softcap,
+                alibi_slopes=alibi_slopes,
+                return_softmax=return_softmax and dropout_p > 0,
+                block_table=None,
+            )
+
+        # store attn forward output to avoid re-computation of attn when activation checkpoint is enabled
+        if gpc.is_forward and gpc.config.selective_checkpoint and layer_idx < _ckpt_block_num:
+            get_offload_manager().insert_fa_output_with_layer(
+                layer_idx=layer_idx, output=(out, out_padded, softmax_lse, S_dmask, rng_state)
+            )
+
+        ctx.save_for_backward(q, k, v, out_padded, softmax_lse, cu_seqlens_q, cu_seqlens_k, rng_state)
+        ctx.dropout_p = dropout_p
+        ctx.max_seqlen_q = max_seqlen_q
+        ctx.max_seqlen_k = max_seqlen_k
+        ctx.softmax_scale = softmax_scale
+        ctx.causal = causal
+        ctx.window_size = window_size
+        ctx.softcap = softcap
+        ctx.alibi_slopes = alibi_slopes
+        ctx.deterministic = deterministic
+        return out if not return_softmax else (out, softmax_lse, S_dmask)
+
+    @staticmethod
+    def backward(ctx, dout, *args):  # pylint: disable=W0613
+        q, k, v, out, softmax_lse, cu_seqlens_q, cu_seqlens_k, rng_state = ctx.saved_tensors
+        dq = torch.empty_like(q)
+        kv_shape = k.shape[:-2] + (2, *k.shape[-2:])
+        dkv = torch.empty(kv_shape, dtype=k.dtype, device=k.device)
+        _flash_attn_varlen_backward(  # pylint: disable=E1121,E1124
+            dout,
+            q,
+            k,
+            v,
+            out,
+            softmax_lse,
+            dq,
+            dkv[:, 0],
+            dkv[:, 1],
+            cu_seqlens_q,
+            cu_seqlens_k,
+            ctx.max_seqlen_q,
+            ctx.max_seqlen_k,
+            ctx.dropout_p,
+            ctx.softmax_scale,
+            ctx.causal,
+            ctx.window_size,
+            ctx.softcap,
+            ctx.alibi_slopes,
+            ctx.deterministic,
+            rng_state=rng_state,
+        )
+        dq = dq[..., : dout.shape[-1]]  # We could have padded the head dimension
+        dkv = dkv[..., : dout.shape[-1]]
+        return dq, dkv, None, None, None, None, None, None, None, None, None, None, None, None, None
+
+
+class FlashAttnVarlenKVPackedFunc_V221(torch.autograd.Function):
+    """
+    Varlen KVPacked Func from Flash Attn v2.2.1.
+    """
+
+    @staticmethod
+    def forward(
+        ctx,
+        q,
+        kv,
+        cu_seqlens_q,
+        cu_seqlens_k,
+        max_seqlen_q,
+        max_seqlen_k,
+        dropout_p,
+        softmax_scale,
+        causal,
+        return_softmax,
+        layer_idx,
+    ):
+        if softmax_scale is None:
+            softmax_scale = q.shape[-1] ** (-0.5)
+
+        k, v = kv[:, 0], kv[:, 1]
+
+        _ckpt_block_num = int(gpc.config.model.checkpoint * gpc.config.isp_num_layers)
+
+        if gpc.is_forward is False and gpc.config.selective_checkpoint and layer_idx < _ckpt_block_num:
+            out, out_padded, softmax_lse, S_dmask, rng_state = get_offload_manager().get_fa_output_with_layer(layer_idx)
+        else:
+            out, q, k, v, out_padded, softmax_lse, S_dmask, rng_state = _flash_attn_varlen_forward(
+                q,
+                k,
+                v,
+                cu_seqlens_q,
+                cu_seqlens_k,
+                max_seqlen_q,
+                max_seqlen_k,
+                dropout_p,
+                softmax_scale,
+                causal=causal,
+                return_softmax=return_softmax and dropout_p > 0,
+            )
+
+        # store attn forward output to avoid re-computation of attn when activation checkpoint is enabled
+        if gpc.is_forward and gpc.config.selective_checkpoint and layer_idx < _ckpt_block_num:
+            get_offload_manager().insert_fa_output_with_layer(
+                layer_idx=layer_idx, output=(out, out_padded, softmax_lse, S_dmask, rng_state)
+            )
+        ctx.save_for_backward(q, k, v, out_padded, softmax_lse, cu_seqlens_q, cu_seqlens_k, rng_state)
+        ctx.dropout_p = dropout_p
+        ctx.max_seqlen_q = max_seqlen_q
+        ctx.max_seqlen_k = max_seqlen_k
+        ctx.softmax_scale = softmax_scale
+        ctx.causal = causal
+        return out if not return_softmax else (out, softmax_lse, S_dmask)
+
+    @staticmethod
+    def backward(ctx, dout, *args):  # pylint: disable=W0613
+        q, k, v, out, softmax_lse, cu_seqlens_q, cu_seqlens_k, rng_state = ctx.saved_tensors
+        dq = torch.empty_like(q)
+        kv_shape = k.shape[:-2] + (2, *k.shape[-2:])
+        dkv = torch.empty(kv_shape, dtype=k.dtype, device=k.device)
+        _flash_attn_varlen_backward(
+            dout,
+            q,
+            k,
+            v,
+            out,
+            softmax_lse,
+            dq,
+            dkv[:, 0],
+            dkv[:, 1],
+            cu_seqlens_q,
+            cu_seqlens_k,
+            ctx.max_seqlen_q,
+            ctx.max_seqlen_k,
+            ctx.dropout_p,
+            ctx.softmax_scale,
+            ctx.causal,
+            rng_state=rng_state,
+        )
+        dq = dq[..., : dout.shape[-1]]  # We could have padded the head dimension
+        dkv = dkv[..., : dout.shape[-1]]
+        return dq, dkv, None, None, None, None, None, None, None, None, None
+
+
+def flash_attn_varlen_kvpacked_func(
+    q,
+    kv,
+    cu_seqlens_q,
+    cu_seqlens_k,
+    max_seqlen_q,
+    max_seqlen_k,
+    dropout_p=0.0,
+    softmax_scale=None,
+    causal=False,
+    window_size=(-1, -1),  # -1 means infinite context window
+    softcap=0.0,  # 0.0 means deactivated
+    alibi_slopes=None,
+    deterministic=False,
+    return_attn_probs=False,
+    layer_idx=0,
+):
+    """dropout_p should be set to 0.0 during evaluation
+    If K, V are already stacked into 1 tensor, this function will be faster than
+    calling flash_attn_func on Q, K, V since the backward pass avoids explicit concatenation
+    of the gradients of K, V.
+    Supports multi-query and grouped-query attention (MQA/GQA) by passing in KV with fewer heads
+    than Q. Note that the number of heads in Q must be divisible by the number of heads in KV.
+    For example, if Q has 6 heads and K, V have 2 heads, head 0, 1, 2 of Q will attention to head
+    0 of K, V, and head 3, 4, 5 of Q will attention to head 1 of K, V.
+    If causal=True, the causal mask is aligned to the bottom right corner of the attention matrix.
+    For example, if seqlen_q = 2 and seqlen_k = 5, the causal mask (1 = keep, 0 = masked out) is:
+        1 1 1 1 0
+        1 1 1 1 1
+    If seqlen_q = 5 and seqlen_k = 2, the causal mask is:
+        0 0
+        0 0
+        0 0
+        1 0
+        1 1
+    If the row of the mask is all zero, the output will be zero.
+    If window_size != (-1, -1), implements sliding window local attention. Query at position i
+    will only attend to keys between
+    [i + seqlen_k - seqlen_q - window_size[0], i + seqlen_k - seqlen_q + window_size[1]] inclusive.
+    Arguments:
+        q: (total_q, nheads, headdim), where total_q = total number of query tokens in the batch.
+        kv: (total_k, 2, nheads_k, headdim), where total_k = total number of key tokens in the batch.
+        cu_seqlens_q: (batch_size + 1,), dtype torch.int32. The cumulative sequence lengths
+           of the sequences in the batch, used to index into q.
+        cu_seqlens_k: (batch_size + 1,), dtype torch.int32. The cumulative sequence lengths
+           of the sequences in the batch, used to index into kv.
+        max_seqlen_q: int. Maximum query sequence length in the batch.
+        max_seqlen_k: int. Maximum key sequence length in the batch.
+        dropout_p: float. Dropout probability.
+        softmax_scale: float. The scaling of QK^T before applying softmax.
+            Default to 1 / sqrt(headdim).
+        causal: bool. Whether to apply causal attention mask (e.g., for auto-regressive modeling).
+        window_size: (left, right). If not (-1, -1), implements sliding window local attention.
+        softcap: float. Anything > 0 activates softcapping attention.
+        alibi_slopes: (nheads,) or (batch_size, nheads), fp32. A bias of
+            (-alibi_slope * |i + seqlen_k - seqlen_q - j|)
+            is added to the attention score of query i and key j.
+        deterministic: bool. Whether to use the deterministic implementation of the backward pass,
+            which is slightly slower and uses more memory. The forward pass is always deterministic.
+        return_attn_probs: bool. Whether to return the attention probabilities. This option is for
+           testing only. The returned probabilities are not guaranteed to be correct
+           (they might not have the right scaling).
+    Return:
+        out: (total, nheads, headdim).
+        softmax_lse [optional, if return_attn_probs=True]: (nheads, total_q_seqlen). The
+            logsumexp of each row of the matrix QK^T * scaling (e.g., log of the softmax
+            normalization factor).
+        S_dmask [optional, if return_attn_probs=True]: (batch_size, nheads, seqlen, seqlen).
+            The output of softmax (possibly with different scaling). It also encodes the dropout
+            pattern (negative means that location was dropped, nonnegative means it was kept).
+    """
+
+    assert gpu_flash_attn_impl is True and flash_attn.__version__ in [
+        "2.2.1",
+        "2.6.3",
+    ], "flash-attn should be installed and version must be v2.2.1 or v2.6.3"
+
+    if flash_attn.__version__ == "2.2.1":
+        return FlashAttnVarlenKVPackedFunc_V221.apply(
+            q,
+            kv,
+            cu_seqlens_q,
+            cu_seqlens_k,
+            max_seqlen_q,
+            max_seqlen_k,
+            dropout_p,
+            softmax_scale,
+            causal,
+            return_attn_probs,
+            layer_idx,
+        )
+
+    return FlashAttnVarlenKVPackedFunc_V263.apply(
+        q,
+        kv,
+        cu_seqlens_q,
+        cu_seqlens_k,
+        max_seqlen_q,
+        max_seqlen_k,
+        dropout_p,
+        softmax_scale,
+        causal,
+        window_size,
+        softcap,
+        alibi_slopes,
+        deterministic,
+        return_attn_probs,
+        layer_idx,
+    )
diff --git a/internlm/model/ops/attention.py b/internlm/model/ops/attention.py
index 604ea77a7..3aec51f55 100644
--- a/internlm/model/ops/attention.py
+++ b/internlm/model/ops/attention.py
@@ -93,13 +93,14 @@
     from flash_attn.flash_attn_interface import (
         flash_attn_varlen_func as _flash_varlen_qkvsplited_func,
     )
-    from flash_attn.flash_attn_interface import (
-        flash_attn_varlen_kvpacked_func as _flash_varlen_kvpacked_func,
-    )
     from flash_attn.flash_attn_interface import (
         flash_attn_varlen_qkvpacked_func as _flash_varlen_qkvpacked_func,
     )
 
+    from ._flash_attn import (
+        flash_attn_varlen_kvpacked_func as _flash_varlen_kvpacked_func,
+    )
+
     gpu_flash_attn_impl = True
 except (ModuleNotFoundError, ImportError):
     gpu_flash_attn_impl = False
@@ -187,6 +188,7 @@ def _flash_varlen_kvpacked_attn(
     dropout_p=0.0,
     softmax_scale=None,
     causal=False,
+    layer_idx=0,
 ):
     # compatible data format: [1, packelen, 3, n_head, headim]
     q, kv = q.squeeze(dim=0), kv.squeeze(dim=0)
@@ -204,6 +206,7 @@ def _flash_varlen_kvpacked_attn(
         dropout_p,
         softmax_scale,
         causal,
+        layer_idx=layer_idx,
     )
 
     return output.unsqueeze(dim=0)
@@ -521,6 +524,7 @@ def _npu_varlen_kvpacked_attn(
     dropout_p=0.0,
     softmax_scale=None,
     causal=False,
+    layer_idx=0,  # pylint: disable=W0613
 ):
     # TODO: support npu native varlen flash attention
     k, v = kv.unbind(dim=2)
@@ -579,6 +583,7 @@ def _deeplink_varlen_kvpacked_attn(
     dropout_p=0.0,
     softmax_scale=None,
     causal=False,
+    layer_idx=0,  # pylint: disable=W0613
 ):
     # compatible data format: [1, packelen, 3, n_head, headim]
     q, kv = q.squeeze(dim=0), kv.squeeze(dim=0)
@@ -1012,7 +1017,17 @@ def _q_kv_with_cu_seqlens(
         extra_args = (key_padding_mask,) if attn_type is AttnType.Torch else ()
 
         return op(
-            q, kv, cu_seqlens_q, cu_seqlens_k, max_seqlen_q, max_seqlen_k, dropout, softmax_scale, causal, *extra_args
+            q,
+            kv,
+            cu_seqlens_q,
+            cu_seqlens_k,
+            max_seqlen_q,
+            max_seqlen_k,
+            dropout,
+            softmax_scale,
+            causal,
+            *extra_args,
+            layer_idx=self.layer_idx,
         )
 
     @forward.register(conditions=(str(QKVPackType.QKVSPLITED), str(CuSeqlenType.With)))
diff --git a/internlm/train/pipeline.py b/internlm/train/pipeline.py
index 79e9caf43..ca11e6898 100644
--- a/internlm/train/pipeline.py
+++ b/internlm/train/pipeline.py
@@ -363,6 +363,7 @@ def initialize_parallel_communicator(model: Union[nn.Module, nn.ModuleList]):
             gpc.config.parallel.weight.overlap,
             gpc.get_group(ParallelMode.WEIGHT),
             is_moe=False,
+            selective_ckpt_offload=gpc.config.get("selective_checkpoint_offload", False),
         )
         # register communicator for isp column parallel linear.
         ColumnParallelLinear.register_cls_communicator(isp_communicator)