Name the card that ran, and say what to install

Two things the first pass got wrong.

The card was named out of whichever listing came first, so a machine
with both a CUDA build and a Vulkan loader could have its card named
from the wrong one. Worse, whisper numbers every device it can see in
one sequence while the handle carries the backend's own index: a
processor-only build lent a Vulkan backend through GGML_BACKEND_PATH
reports "device 1: Vulkan0", and reading that listing by the handle's
digit names whatever sat in slot zero. The backend's own enumeration is
asked first now, because it is the only one indexed the way the handle
is, and whisper's listing is a fallback taken only when it names
exactly one card.

And "this build carries no graphics backend" left the reader with
nowhere to go. It is the one case with a fix worth naming: whisper.cpp
publishes no build that reaches a card on Linux, and program_path runs
a copy from the system ahead of the downloaded one, so installing one
is the whole remedy. Server.state() now says which copy is running,
and the line says so only when it is Dikte's own download; a system
build that cannot reach the card gets the shorter sentence, since
installing it again would change nothing.

Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_019zqCqhmeaNT6m1GPp8ZWPp

tests/test_ggml.py

@@ -608,6 +608,36 @@ load_tensors: offloaded 0/29 layers to GPU
 """
 
 
+# A downloaded processor-only build pointed at the system's Vulkan backend
+# through GGML_BACKEND_PATH. whisper numbers every device it can see in one
+# sequence, so the card is its device 1 while still being Vulkan0.
+WHISPER_LENT_BACKEND = """\
+load_backend: loaded CPU backend from /data/bin/whisper/libggml-cpu-haswell.so
+ggml_vulkan: Found 1 Vulkan devices:
+ggml_vulkan: 0 = AMD Radeon RX 6600 (RADV NAVI23) (radv) | uma: 0
+load_backend: loaded Vulkan backend from /usr/lib/ggml/libggml-vulkan.so
+whisper_model_load:      Vulkan0 total size =   189.49 MB
+whisper_backend_init_gpu: device 0: CPU (type: 0)
+whisper_backend_init_gpu: device 1: Vulkan0 (type: 1)
+whisper_backend_init_gpu: found GPU device 1: Vulkan0 (type: 1, cnt: 0)
+whisper_backend_init_gpu: using Vulkan0 backend
+"""
+
+# Two cards, and the one that ran is not the one in the slot the handle names.
+# Reading whisper's listing by the handle's digit would name the other card.
+WHISPER_TWO_CARDS = """\
+ggml_vulkan: Found 1 Vulkan devices:
+ggml_vulkan: 0 = AMD Radeon RX 6600 (RADV NAVI23) (radv) | uma: 0
+load_backend: loaded CUDA backend from /opt/whisper/libggml-cuda.so
+load_backend: loaded Vulkan backend from /opt/whisper/libggml-vulkan.so
+load_backend: loaded CPU backend from /opt/whisper/libggml-cpu-haswell.so
+whisper_model_load:      Vulkan0 total size =   189.49 MB
+whisper_backend_init_gpu: device 0: NVIDIA GeForce RTX 4070 (type: 1)
+whisper_backend_init_gpu: device 1: Vulkan0 (type: 1)
+whisper_backend_init_gpu: using Vulkan0 backend
+"""
+
+
 class WhatItRunsOn(Local):
     """Reading the backend back out of the log the server wrote."""
 
@@ -648,6 +678,18 @@ class WhatItRunsOn(Local):
         self.assertNotIn("(radv)",
                          self.read(ggml.WHISPER, WHISPER_VULKAN).device)
 
+    def test_a_card_numbered_one_way_and_handled_another_is_still_named(self):
+        accel = self.read(ggml.WHISPER, WHISPER_LENT_BACKEND)
+        self.assertEqual(accel.backend, "Vulkan")
+        self.assertEqual(accel.device, "AMD Radeon RX 6600 (RADV NAVI23)")
+
+    def test_the_card_named_is_the_one_the_handle_belongs_to(self):
+        # whisper's device 0 is the other card. The handle is Vulkan0, and
+        # Vulkan's own device 0 is the AMD one.
+        accel = self.read(ggml.WHISPER, WHISPER_TWO_CARDS)
+        self.assertEqual(accel.device, "AMD Radeon RX 6600 (RADV NAVI23)")
+        self.assertNotIn("NVIDIA", ggml.accel_detail(accel))
+
     def test_a_card_that_failed_to_start_is_not_a_card_in_use(self):
         # It was listed, it was tried, it did not work, and whisper went on
         # without it. The listing alone would have called this a graphics card.
@@ -694,6 +736,14 @@ class WhatItRunsOn(Local):
         self.assertEqual(ggml.accel_detail(self.read(ggml.WHISPER, WHISPER_CPU)),
                          "CPU")
 
+    def test_which_copy_is_running_decides_what_advice_is_worth_giving(self):
+        mine = ggml.BIN_DIR / "whisper" / "b1" / "whisper-server"
+        mine.parent.mkdir(parents=True, exist_ok=True)
+        mine.write_text("#!/bin/sh\n")
+        self.assertTrue(ggml.is_downloaded(str(mine)))
+        self.assertFalse(ggml.is_downloaded("/usr/bin/whisper-server"))
+        self.assertFalse(ggml.is_downloaded(""))
+
     def test_nothing_is_running_is_not_a_backend(self):
         self.assertEqual(ggml.accel_kind({"running": False, "backend": "CUDA"}),
                          "off")