Reinstate exl2 with tp (huggingface#1490)

# What does this PR do?

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Fixes # (issue)


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- [ ] This PR fixes a typo or improves the docs (you can dismiss the
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integration-tests/models/__snapshots__/test_flash_starcoder_gptq/test_flash_starcoder_gptq_default_params.json

@@ -16,60 +16,60 @@
       },
       {
         "id": 21017,
-        "logprob": -9.09375,
+        "logprob": -9.0859375,
         "text": "ometric"
       },
       {
         "id": 81,
-        "logprob": -0.25976562,
+        "logprob": -0.25830078,
         "text": "_"
       },
       {
         "id": 6009,
-        "logprob": -2.2148438,
+        "logprob": -2.1875,
         "text": "mean"
       },
       {
         "id": 26,
-        "logprob": -0.3010254,
+        "logprob": -0.30004883,
         "text": "("
       },
       {
         "id": 62,
-        "logprob": -5.6757812,
+        "logprob": -5.6171875,
         "text": "L"
       },
       {
         "id": 44,
-        "logprob": -3.0898438,
+        "logprob": -3.078125,
         "text": ":"
       },
       {
         "id": 1682,
-        "logprob": -0.6791992,
+        "logprob": -0.68066406,
         "text": " List"
       },
       {
         "id": 77,
-        "logprob": -0.38891602,
+        "logprob": -0.38745117,
         "text": "["
       },
       {
         "id": 1808,
-        "logprob": -0.92041016,
+        "logprob": -0.9453125,
         "text": "float"
       },
       {
         "id": 10794,
-        "logprob": -2.5390625,
+        "logprob": -2.5371094,
         "text": "]):"
       }
     ],
     "seed": 0,
     "tokens": [
       {
         "id": 284,
-        "logprob": 0.0,
+        "logprob": -0.051635742,
         "special": false,
         "text": "\n   "
       },
@@ -81,7 +81,7 @@
       },
       {
         "id": 11665,
-        "logprob": -1.6005859,
+        "logprob": -1.2236328,
         "special": false,
         "text": " reduce"
       },
@@ -159,7 +159,7 @@
       },
       {
         "id": 203,
-        "logprob": -0.11968994,
+        "logprob": -0.12695312,
         "special": false,
         "text": "\n"
       },

server/text_generation_server/utils/gptq/exllamav2.py

@@ -185,6 +185,10 @@ def post_init(self, temp_dq):
             "g_idx": self.g_idx,
         }
         temp_dq = temp_dq.get_scratch_slice(self.temp_dq_size())
+
+        # We NEED to keep a pointer on Python side, otherwise the garbage collector will mess with us,
+        # and `Memory access fault by GPU node-2` will EAT you.
+        self.temp_dq = temp_dq
         self.q_handle = ext_make_q_matrix(self.q_tensors, temp_dq)
 
     def forward(self, x, force_cuda=False):

server/text_generation_server/utils/layers.py

@@ -35,12 +35,12 @@
 HAS_EXLLAMA = False
 CAN_EXLLAMA = major >= 8
 V2 = os.getenv("EXLLAMA_VERSION", "2") == "2"
-if V2 and int(os.getenv("WORLD_SIZE", "1")) > 1:
-    V2 = False
-    log_once(
-        logger.warning,
-        "Disabling exllama v2 and using v1 instead because there are issues when sharding",
-    )
+# if V2 and int(os.getenv("WORLD_SIZE", "1")) > 1:
+#     V2 = False
+#     log_once(
+#         logger.warning,
+#         "Disabling exllama v2 and using v1 instead because there are issues when sharding",
+#     )
 
 if os.getenv("DISABLE_EXLLAMA") == "True":
     HAS_EXLLAMA = False