From bef001c1515a13a9b8e361a5a7d372fc2e01094c Mon Sep 17 00:00:00 2001 From: Takoroka <137927095+Takoroka@users.noreply.github.com> Date: Fri, 30 Oct 2026 15:39:08 -0400 Subject: nx2: read command lists the GPU wrote from the GPU's copy Mario Kart World runs small command lists (20-byte entries) that its culling dispatches fill in each frame. Accurate GPU mode reads every command list through the caches; Fast mode reads guest memory directly (on the split's front thread too), where those entries were still the words of an older frame, so the draws behind them were left out: the trees around the courses vanished in Fast mode only. The buffer cache now also marks the device pages the GPU writes (shader stores, copies of GPU-written data) in a bitmap the split's front can read. A command list on such a page waits for the back to run what was queued before it and is flushed when its words are still only in host buffers. In a race that is ~5% of command lists (13,500 a second of 262,000) and ~400 flushes a second. --- src/video_core/buffer_cache/buffer_cache.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'src/video_core/buffer_cache/buffer_cache.h') diff --git a/src/video_core/buffer_cache/buffer_cache.h b/src/video_core/buffer_cache/buffer_cache.h index 42d7ba066d..a8f1edc68d 100644 --- a/src/video_core/buffer_cache/buffer_cache.h +++ b/src/video_core/buffer_cache/buffer_cache.h @@ -17,6 +17,7 @@ #include "video_core/buffer_cache/buffer_cache_base.h" #include "video_core/guest_memory.h" #include "video_core/host1x/gpu_device_memory_manager.h" +#include "video_core/nx2.h" #include "video_core/nx2_profile.h" #include "video_core/texture_cache/util.h" @@ -289,6 +290,9 @@ bool BufferCache
::DMACopy(GPUVAddr src_address, GPUVAddr dest_address, u64 am const bool has_new_downloads = tmp_intervals.size() != 0; for (const auto& pair : tmp_intervals) { gpu_modified_ranges.Add(pair.first, pair.second); + if (Tegra::g_nx2_ampere.load(std::memory_order_relaxed)) { + Tegra::Nx2MarkGpuWritten(pair.first, pair.second); + } } const auto& copy = copies[0]; src_buffer.MarkUsage(copy.src_offset, copy.size); @@ -1606,6 +1610,9 @@ void BufferCache
::MarkWrittenBuffer(BufferId buffer_id, DAddr device_addr, u3
if (AsyncBufferDownloads()) {
uncommitted_gpu_modified_ranges.Add(device_addr, size);
}
+ if (Tegra::g_nx2_ampere.load(std::memory_order_relaxed)) {
+ Tegra::Nx2MarkGpuWritten(device_addr, size);
+ }
}
template ::TickFrame() {
// title 1's buffers were ~200 MiB of an 8 GB GPU's ~6.8 GB in use, yet this collector
// ran aggressively every frame on the device-wide figure, evicting up to 64 buffers (and
// downloading the GPU-written ones, ~5% of the GPU thread) that were recreated later.
- // Collect when the buffers themselves are large.
- if (buffer_bytes >= 1_GiB) {
- RunGarbageCollector(buffer_bytes >= 2_GiB);
+ // Collect when the buffers themselves are large. At 1 GiB it held geometry of scenes
+ // long gone: title 1's title screen grew to ~0.9 GB of buffers in ten minutes.
+ if (buffer_bytes >= 512_MiB) {
+ RunGarbageCollector(buffer_bytes >= 1_GiB);
}
} else if (total_used_memory >= minimum_memory) {
RunGarbageCollector(total_used_memory >= critical_memory);
--
cgit v1.2.3
From 86968cb5ce3195cb131eeb0ef68d2d8a4860f7df Mon Sep 17 00:00:00 2001
From: Takoroka <137927095+Takoroka@users.noreply.github.com>
Date: Sun, 1 Nov 2026 08:42:26 -0500
Subject: buffer_cache: mark guest memory large buffer uploads came from cold
Like the texture cache's uploads: guest ranges of 256 KiB or more uploaded
to the host GPU are mostly geometry the guest rarely reads again, so every
600 frames they are marked cold and the OS pages them out first when it
needs RAM.
(cherry picked from commit 5c942a5158a0f9769553eeba21b6121f277d0dc5)
---
src/video_core/buffer_cache/buffer_cache.h | 11 +++++++++++
src/video_core/buffer_cache/buffer_cache_base.h | 2 ++
2 files changed, 13 insertions(+)
(limited to 'src/video_core/buffer_cache/buffer_cache.h')
diff --git a/src/video_core/buffer_cache/buffer_cache.h b/src/video_core/buffer_cache/buffer_cache.h
index 42d7ba066d..633f8760e4 100644
--- a/src/video_core/buffer_cache/buffer_cache.h
+++ b/src/video_core/buffer_cache/buffer_cache.h
@@ -100,6 +100,12 @@ void BufferCache ::TickFrame() {
return;
}
runtime.TickFrame(slot_buffers);
+ if (frame_tick % 600 == 0 && !uploaded_buffer_ranges.empty()) {
+ for (const auto& [address, size] : uploaded_buffer_ranges) {
+ device_memory.HintCold(address, size);
+ }
+ uploaded_buffer_ranges.clear();
+ }
if (static u64 frames{}; ++frames % 600 == 0) {
u64 total{};
size_t count{};
@@ -1923,6 +1929,11 @@ void BufferCache ::MappedUploadMemory([[maybe_unused]] Buffer& buffer,
u8* const src_pointer = staging_pointer.data() + copy.src_offset;
const DAddr device_addr = buffer.CpuAddr() + copy.dst_offset;
device_memory.ReadBlockUnsafe(device_addr, src_pointer, copy.size);
+ // Large uploads are mostly geometry the host GPU now has its own copy of: TickFrame
+ // marks their guest memory cold (see TextureCache::RefreshContents).
+ if (copy.size >= 256_KiB) {
+ uploaded_buffer_ranges.emplace_back(device_addr, copy.size);
+ }
// Apply the staging offset
copy.src_offset += upload_staging.offset;
}
diff --git a/src/video_core/buffer_cache/buffer_cache_base.h b/src/video_core/buffer_cache/buffer_cache_base.h
index 45a1836341..0db8bdb1eb 100644
--- a/src/video_core/buffer_cache/buffer_cache_base.h
+++ b/src/video_core/buffer_cache/buffer_cache_base.h
@@ -549,6 +549,8 @@ private:
size_t immediate_buffer_capacity = 0;
Common::ScratchBuffer ::BindHostGraphicsUniformBuffers(size_t stage) {
template ::BindHostGraphicsUniformBuffer(size_t stage, u32 index, u32 binding_index, bool needs_bind) {
++channel_state->uniform_cache_shots[0];
+ // Bank 24 (root table 0, NVN2's push constants) is read from bank 17, which such games do not
+ // bind: stream the table's current words as that buffer.
+ if (index == 17 && maxwell3d->root_tables.loaded && channel_state->uniform_buffers[stage][index].size == 0) {
+ const auto& words = maxwell3d->root_tables.tables[0];
+ const u32 size = (*channel_state->uniform_buffer_sizes)[stage][index];
+ const u32 copied = (std::min)(size, static_cast ::BindGraphicsUniformBuffer(size_t stage, u32 index, GPUVAddr gpu_addr,
u32 size) {
const std::optional ::BindGraphicsUniformBuffer(size_t stage, u32 index, GPUVAddr
template ::DisableGraphicsUniformBuffer(size_t stage, u32 index) {
- channel_state->uniform_buffers[stage][index] = NULL_BINDING;
+ auto& current = channel_state->uniform_buffers[stage][index];
+ if (current.device_addr == 0 && current.size == 0 && !current.buffer_id) [[likely]] {
+ return;
+ }
+ current = NULL_BINDING;
}
template ::UpdateDrawIndirect() {
template ::UpdateUniformBuffers(size_t stage) {
+ if (channel_state->enabled_uniform_buffer_masks[stage] == 0) [[likely]] {
+ return;
+ }
ForEachEnabledBit(channel_state->enabled_uniform_buffer_masks[stage], [&](u32 index) {
Binding& binding = channel_state->uniform_buffers[stage][index];
if (binding.buffer_id) {
@@ -1531,6 +1542,9 @@ void BufferCache ::UpdateUniformBuffers(size_t stage) {
template ::UpdateStorageBuffers(size_t stage) {
+ if (channel_state->enabled_storage_buffers[stage] == 0) [[likely]] {
+ return;
+ }
ForEachEnabledBit(channel_state->enabled_storage_buffers[stage], [&](u32 index) {
// Resolve buffer
Binding& binding = channel_state->storage_buffers[stage][index];
@@ -1543,6 +1557,9 @@ void BufferCache ::UpdateStorageBuffers(size_t stage) {
template ::UpdateTextureBuffers(size_t stage) {
+ if (channel_state->enabled_texture_buffers[stage] == 0) [[likely]] {
+ return;
+ }
ForEachEnabledBit(channel_state->enabled_texture_buffers[stage], [&](u32 index) {
Binding& binding = channel_state->texture_buffers[stage][index];
binding.buffer_id = FindBuffer(binding.device_addr, binding.size, false);
--
cgit v1.2.3
From a407703f6d29a5ab73328b4ededb12cf29b2758d Mon Sep 17 00:00:00 2001
From: Whovian64 <86082882+whovian64@users.noreply.github.com>
Date: Mon, 2 Nov 2026 02:45:39 -0500
Subject: Linux and AMD: BC3 flashing on RADV, ASTC decode stalls, lower RAM
usage, a buffer cache crash (#260)
* host_memory: punch holes in the backing on Linux instead of zero filling freed memory
Freeing guest memory zero filled the memfd backing with memset, which
commits every page it touches. fallocate(PUNCH_HOLE) hands the pages back
to the kernel instead, and they read as zero afterwards. Only the partial
pages at the ends are still cleared by hand.
Mario Kart World on Linux (RX 9070 XT, 31 GB): peak RSS 23.1 -> 15.9 GB.
EDEN_PUNCH_HOLE=0 restores the memset.
Assisted-by: Claude Opus 5.5 (debugging, profiling and code drafts)
* fiber: don't zero fill the stacks, untouched pages stay unbacked
The value initialised stack arrays were zero filled when each fiber was
made, which commits the whole stack. Left uninitialised, the pages a
fiber never touches stay unbacked. Together with the descriptor ring
change, about 1.2 GB less RSS in Mario Kart World.
Assisted-by: Claude Opus 5.5 (debugging, profiling and code drafts)
* vulkan: don't zero fill the descriptor update ring
Same as the fiber stacks: make_unique value initialised the whole ring
for every frame in flight. Entries are always written before they are
read, so allocate it without initialising it.
Assisted-by: Claude Opus 5.5 (debugging, profiling and code drafts)
* vulkan: wait for the GPU after an ASTC transcode decode like the other ASTC decodes
TranscodeAstcToBcn (astc_recompression Bc1/Bc3 with GPU decode) was the
only ASTC decode recorded with wait = false. On RADV (RX 9070 XT, Mesa)
Mario Kart World with BC3 flashed heavily all over the screen, while the
uncompressed GPU decode, which waits, did not. CPU decode with BC3 does
not flash either. Waiting after the transcode removes the flashing; full
pipeline barriers around its copy did not, so the wait hides a race
somewhere else rather than fixing one in the transcode itself.
Assisted-by: Claude Opus 5.5 (debugging, profiling and code drafts)
* vulkan: submit after an ASTC decode instead of waiting for the GPU by default
Every ASTC decode ended with scheduler.Finish(). Over a 19 minute Mario
Kart World Grand Prix that stalled the GPU thread 30.7 s in total, up to
1.2 s out of every 5 s while new textures stream in (track sections,
race starts), which is where the hitches were. Flushing keeps the
ordering that stops the BC3 flashing on RADV without the CPU waiting:
no flashing in play, and frames over 100 ms went from dozens to 3 in
about 7 minutes. EDEN_NX2_ASTC_FLUSH=0 restores the wait.
Assisted-by: Claude Opus 5.5 (debugging, profiling and code drafts)
* texture_cache: over the expected use, evict costly images unused for 1800 frames first
The collector never deletes CostlyLoad images outside aggressive mode, so
once a cup moves on, the previous tracks' textures stay resident and the
cache sits over its expected use deleting the cheap images still in use.
When over the expected use, costly images unused for 1800 frames (half a
minute) now go first.
Mario Kart World Grand Prix on an RX 9070 XT: frames over 20 ms 8.8% ->
4.0%, 58.7 fps average. EDEN_NX2_TC_OLD_AGE= ::MarkWrittenBuffer(BufferId buffer_id, DAddr device_addr, u3
template ::FindBuffer(DAddr device_addr, u32 size, bool sparse_compatible) {
- if (device_addr == 0) {
+ const u64 page = device_addr >> CACHING_PAGEBITS;
+ if (device_addr == 0 || page >= page_table.size()) {
return NULL_BUFFER_ID;
}
- const u64 page = device_addr >> CACHING_PAGEBITS;
const BufferId buffer_id = page_table[page];
if (buffer_id) {
Buffer& buffer = slot_buffers[buffer_id];
diff --git a/src/video_core/renderer_vulkan/vk_compute_pass.cpp b/src/video_core/renderer_vulkan/vk_compute_pass.cpp
index 691be728d2..cb8dcde42f 100644
--- a/src/video_core/renderer_vulkan/vk_compute_pass.cpp
+++ b/src/video_core/renderer_vulkan/vk_compute_pass.cpp
@@ -801,11 +801,11 @@ void ASTCDecoderPass::AssembleInto(const VideoCommon::ImageInfo& info, u32 skip,
cmdbuf.PipelineBarrier(VK_PIPELINE_STAGE_COMPUTE_SHADER_BIT,
vk::PIPELINE_STAGE_GRAPHICS_COMPUTE, 0, image_barrier);
});
- // Each decode ends with the GPU thread waiting for the host GPU to go idle. Measured here
- // (count and time per 5 s); EDEN_NX2_ASTC_FLUSH=1 submits without waiting instead.
+ // Each decode ends with a submit to the host GPU. Measured here
+ // (count and time per 5 s); EDEN_NX2_ASTC_FLUSH=0 waits for the host GPU to go idle instead.
static const bool flush_only = [] {
const char* value = std::getenv("EDEN_NX2_ASTC_FLUSH");
- return value != nullptr && value[0] == '1';
+ return value == nullptr || value[0] != '0';
}();
if (!target.wait) {
return;
diff --git a/src/video_core/renderer_vulkan/vk_texture_cache.cpp b/src/video_core/renderer_vulkan/vk_texture_cache.cpp
index 4e428229f6..b0e5eacb32 100644
--- a/src/video_core/renderer_vulkan/vk_texture_cache.cpp
+++ b/src/video_core/renderer_vulkan/vk_texture_cache.cpp
@@ -4267,7 +4267,7 @@ void TextureCacheRuntime::TranscodeAstcToBcn(
.aspect_mask = VK_IMAGE_ASPECT_COLOR_BIT,
.initialized = false,
.level_view = [&pending](s32 level) { return *pending.views[level]; },
- .wait = false,
+ .wait = true,
},
map, swizzles);
diff --git a/src/video_core/renderer_vulkan/vk_update_descriptor.cpp b/src/video_core/renderer_vulkan/vk_update_descriptor.cpp
index 742a8d9969..29f3ee71a1 100644
--- a/src/video_core/renderer_vulkan/vk_update_descriptor.cpp
+++ b/src/video_core/renderer_vulkan/vk_update_descriptor.cpp
@@ -20,10 +20,10 @@ UpdateDescriptorQueue::UpdateDescriptorQueue(const Device& device_, size_t frame
bool supports_descriptor_buffer_)
: device{device_}, frame_payload_size{frame_payload_size_},
supports_descriptor_buffer{supports_descriptor_buffer_},
- payload(frame_payload_size_ * FRAMES_IN_FLIGHT)
+ payload(std::make_unique_for_overwrite ::RunGarbageCollector() {
bool high_priority_mode = false;
bool aggressive_mode = false;
+ bool evict_old_costly = false;
u64 ticks_to_destroy = 0;
size_t num_iterations = 0;
const auto Configure = [&](bool allow_aggressive) {
@@ -139,7 +140,8 @@ void TextureCache ::RunGarbageCollector() {
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) {
+ const auto Cleanup = [this, &num_iterations, &high_priority_mode, &aggressive_mode,
+ &evict_old_costly](ImageId image_id) {
if (num_iterations == 0) {
return true;
}
@@ -149,7 +151,8 @@ void TextureCache ::RunGarbageCollector() {
return false;
}
const bool must_download = IsDownloadable(image) && False(image.flags & ImageFlagBits::BadOverlap);
- if ((!aggressive_mode && True(image.flags & ImageFlagBits::CostlyLoad)) || (!high_priority_mode && must_download)) {
+ if ((!aggressive_mode && !evict_old_costly && True(image.flags & ImageFlagBits::CostlyLoad)) ||
+ (!high_priority_mode && must_download)) {
return false;
}
if (must_download) {
@@ -176,6 +179,15 @@ void TextureCache ::RunGarbageCollector() {
return false;
};
Configure(false);
+ static const u64 old_age = [] {
+ const char* value = std::getenv("EDEN_NX2_TC_OLD_AGE");
+ return value != nullptr ? std::strtoull(value, nullptr, 10) : 1800ULL;
+ }();
+ if (high_priority_mode && old_age != 0 && frame_tick > old_age) {
+ evict_old_costly = true;
+ lru_cache.ForEachItemBelow(frame_tick - old_age, Cleanup);
+ evict_old_costly = false;
+ }
lru_cache.ForEachItemBelow(frame_tick - ticks_to_destroy, Cleanup);
if (total_used_memory >= critical_memory) {
Configure(true);
--
cgit v1.2.3