texture_cache: count evictions that download; EDEN_NX2_TC_MIN_AGE knob

The collector's periodic log now also counts evictions that downloaded the image first
(each a full GPU wait). EDEN_NX2_TC_MIN_AGE=<frames> keeps images used more recently
than that (a VRAM thrash test on 8 GB: 120 frames made no difference over three runs).

1 files changed, 10 insertions, 2 deletions

diff --git a/src/video_core/texture_cache/texture_cache.h b/src/video_core/texture_cache/texture_cache.h
index fb8adef161..b95d9d8a39 100644
--- a/src/video_core/texture_cache/texture_cache.h
+++ b/src/video_core/texture_cache/texture_cache.h
@@ -129,6 +129,12 @@ void TextureCache<P>::RunGarbageCollector() {
         high_priority_mode = total_used_memory >= expected_memory;
         aggressive_mode = allow_aggressive && total_used_memory >= critical_memory;
         ticks_to_destroy = aggressive_mode ? 10ULL : high_priority_mode ? 25ULL : 50ULL;
+        // EDEN_NX2_TC_MIN_AGE=<frames>: never evict images used more recently (thrash tests).
+        static const u64 min_age = [] {
+            const char* value = std::getenv("EDEN_NX2_TC_MIN_AGE");
+            return value != nullptr ? std::strtoull(value, nullptr, 10) : 0ULL;
+        }();
+        ticks_to_destroy = (std::max)(ticks_to_destroy, min_age);
         num_iterations = aggressive_mode ? 40 : (high_priority_mode ? 20 : 10);
     };
     const auto Cleanup = [this, &num_iterations, &high_priority_mode, &aggressive_mode](ImageId image_id) {
@@ -150,6 +156,7 @@ void TextureCache<P>::RunGarbageCollector() {
             image.DownloadMemory(map, copies);
             runtime.Finish();
             SwizzleImage(*gpu_memory, image.gpu_addr, image.info, copies, map.mapped_span, swizzle_data_buffer);
+            ++gc_download_deletes;
         }
         if (True(image.flags & ImageFlagBits::Tracked)) {
             UntrackImage(image, image_id);
@@ -269,8 +276,9 @@ void TextureCache<P>::TickFrame() {
         if constexpr (requires { runtime.LogMemoryStatistics(); }) {
             runtime.LogMemoryStatistics();
         }
-        LOG_INFO(HW_GPU, "Texture cache last 600 frames: created {} images, deleted {} (collector {}, {} costly), {} async decodes, ASTC {} opaque / {} alpha",
+        LOG_INFO(HW_GPU, "Texture cache last 600 frames: created {} images, deleted {} (collector {}, {} costly, {} downloaded), {} async decodes, ASTC {} opaque / {} alpha",
                  images_created, images_deleted, gc_deletes + gc_costly_deletes, gc_costly_deletes,
+                 gc_download_deletes,
                  async_decodes_queued, astc_opaque_images, astc_alpha_images);
         astc_opaque_images = astc_alpha_images = 0;
         std::vector<std::pair<u32, u64>> shapes;
@@ -284,7 +292,7 @@ void TextureCache<P>::TickFrame() {
                      created_shapes[key].second);
         }
         created_shapes.clear();
-        gc_deletes = gc_costly_deletes = async_decodes_queued = 0;
+        gc_deletes = gc_costly_deletes = gc_download_deletes = async_decodes_queued = 0;
         images_created = images_deleted = 0;
     }
     if (total_used_memory > minimum_memory) {