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hip: bypass memory pool for FA f16 temp buffers#92

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TheTom merged 312 commits intomasterfrom
fix/hip-fa-pool-retention
Apr 20, 2026
Merged

hip: bypass memory pool for FA f16 temp buffers#92
TheTom merged 312 commits intomasterfrom
fix/hip-fa-pool-retention

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@TheTom TheTom commented Apr 20, 2026

Backport of upstream draft PR ggml-org#22094.

Bypasses the legacy memory pool for flash attention f16 temp buffers on HIP/ROCm to prevent OOM with quantized KV cache types (q8_0, q4_0).

Includes code review feedback: deleted copy constructor and assignment operator on the RAII wrapper to prevent accidental double-free.

Single file: ggml/src/ggml-cuda/fattn-common.cuh, #ifdef GGML_USE_HIP only.

Refs: ggml-org#22107, ROCm/rocm-systems#2516

0cc4m and others added 30 commits April 9, 2026 07:31
actions/labeler@v6 removed the `all:` / `any:` composition keys.
The `server/webui` and `server` entries used `all:` to combine
`any-glob-to-any-file` with negated `all-globs-to-all-files`,
which now errors on every PR with:

    Unknown config options were under "changed-files": all

Flatten both entries to a single `any-glob-to-any-file`. PRs
touching both webui and other server files will now receive both
labels instead of only `server/webui`.

Co-authored-by: Marxist-Leninist <noreply@users.noreply.github.com>
* sycl : add flash-attn support for head size 512

This patch extends the SYCL Flash Attention implementation to support head sizes (DKQ/DV) of 512.

Changes:
- Added DKQ/DV 512 cases to both tile and vector Flash Attention kernels.
- Updated kernel selection logic to allow vector kernels for head sizes up to 512 (previously 256).
- Removed unused/redundant AMD and RDNA-specific configuration functions in `fattn-tile.hpp`.
- Refactored `ggml_backend_sycl_buffer_init_tensor` to use a switch statement for clearer tensor extra buffer initialization.
- Added necessary template instances for the new 512 head size across various quantization types.

* remove defunct mxfp4 reorder from setting buffer type
…lf-filtering (ggml-org#21623)

* feat: jinja engine improvements for reka-edge

Port three Jinja engine improvements needed for the reka-edge model:
1. Python-style string repetition ("ab" * 3 → "ababab")
2. ensure_ascii=true support for tojson filter (escapes non-ASCII to \uXXXX)
3. int() builtin on value_int_t (identity, needed for Reka Edge template)

* fix: escape invalid utf8 bytes when ensure_ascii=true

The json_ensure_ascii_preserving_format function does not correctly
handle an edge case where if UTF-8 parsing fails, it adds the non-ascii
character back to the output as a raw byte.

This commit fixes that by adding the unicode standard replacement
character \\ufffd to the output instead. This is the standard behavior
for various programming languages like Python, Rust, Go, etc.

* chore: address PR comments

1. Add todo comment for supporting string repetition for array/tuples
2. Add support for float identity operation
3. Move invalid ascii test case to test_fuzzing

* chore: accept suggestion for common/jinja/value.cpp

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>

---------

Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
* YATF (Yet Another Tokenizer Fix) for Gemma 4. With tests!
* Remove unnecessary hash  from update script.
* minor: move constant
* convert gguf

* clip impl

* fix conversion

* wip

* corrections

* update docs

* add gguf to test script
* model: fix multimodal padding token for gemma3n/gemma4

* nits
* common : simplify autoparser tagged parser rules

* cont : remove upper limit on optional args

* cont : revert changes to parsing at the end

* cont : undo arbitrary ordering of optional args

* cont : fix uninitialized required parameters

* revert to simplify merge

* re-apply patches

* restore flexible optional arg ordering tests
* common : fix ambiguous grammar rule in gemma4

* cont : fix missing comma...
* webui: make Enter to send chat a setting

* Shorten description

* Use isMobile hook from $lib/hooks

* Rebuild static output
* requirements : update transformers to 5.5.0

This commit updates the transformers dependency to version 5.5.0.

The motivation for this is that transformers 5.5.0 includes support for
Gemma4 and is required to be able to convert Gemma4 models. This is also
causing issues for user of gguf-my-repo.

Refs: https://huggingface.co/spaces/ggml-org/gguf-my-repo/discussions/202

* fix huggingface_hub version

* set version of transformers to 5.5.0

* convert : add ty ignore directives to convert_hf_to_gguf.py

This commit adds `ty: ignore` directives to transformers tokenizers
field/methods to avoid type check errors. There might be better ways to
handle this and perhaps this can be done in a follow up commit.

The motivation for this is that it looks like in transformers 5.5.0
AutoTokenizer.from_pretrained can return generic tokenizer types or None
and the type checker now produces an error when the conversion script
accesses field like tokenizer.vocab.

* convert : add ty ignore to suppress type check errors

* convert : remove incorrect type ignores

* convert : fix remaining python checks

I was running a newer version of ty locally but I've switched to
version 0.0.26 which is what CI uses and I was then able to reproduce
the errors. Sorry about the noise.

* update transformers version to 5.5.1
…y all return cudaError_t) (ggml-org#21676)

Co-authored-by: Stanisław Szymczyk <sszymczy@gmail.com>
)

* ggml: backend-agnostic tensor parallelism

* support for GPT-OSS, Qwen 3 MoE

* partial Vulkan fix

* add support for 4/8 GPUs

* unconditional peer access

* re-use buffers + ggml contexts

* fix output pattern

* NCCL support

* GGML: HIP: add RCCL support

* Remove shfl and AllReduce from backend interface

* move allocation workaround out of ggml-alloc.c

* 2d tensor set/get support

* Fix the seg fault without NCCL

* Apply suggestion from JohannesGaessler

* support for tensor dims % n_devs != 0

* fix view_offs scaling

* arbitrary num. of GPUs/tensor split

* fix compilation

* better granularity estimate

* Support device-specific host buffer types if all underlying backends expose the same type. This allows using pinned memory instead of pageable memory for CUDA.

Fix compilation errors.

* partial Qwen 3 Next support

* Fix qwen3 30b (#8)

* Fix crash with Qwen-30B-A3B Q4_0

Qwen-30B-A3B Q4_0 has an intermediate dimension of 768. Using a granularity of 256 forces an uneven split between GPUs, which is not supported by the current implementation.

* Decide block size based on tensor quantization type

* Fix crashes due to KV cache serialization (#9)

KV cache serialization requires non-zero offsets on the tensor. Add support in the meta backend to set/get a tensor with a non-zero offset.

* metal : fix build (#7)

* static memory allocations, fix usage count

* fix tensor granularity

* more even memory distribution

* use BF16 for allreduce

* rebase fixup

* better error message for unsupported architectures

* Fix device mismatch during scatter of allReduce. (#11)

There is a mismatch between the dst buffer device and the backend device, causing the use of sync copies

* Enable the previous allreduce implementation. It is better in both perf and stability (#12)

* delay AllReduce for Moe for less I/O

* build : clean-up compile warnings

* backend : move most of the meta backend API to ggml-backend-impl.h

* cont : hide unused public API in the implementation

* llama : use llama_device + remove ggml_backend_dev_is_meta()

* ggml-backend : remove unused alloc include

* minor : remove regex include

* ggml : introduce ggml-ext.h for staging new APIs

* rebase fixup

* fix tests

* llama : more robust logic for determining Meta devices (#16)

* llama : more robust logic for determining Meta devices

* cont : fix devs size check

Co-authored-by: Johannes Gäßler <johannesg@5d6.de>

* cont : fix log type

Co-authored-by: Johannes Gäßler <johannesg@5d6.de>

---------

Co-authored-by: Johannes Gäßler <johannesg@5d6.de>

* disable roundtrip for meta backend

* fix arch selection

* Qwen 3.5 support

* fix Gemma 4 MoE

* fix OpenVino, SYCL

* fix test-llama-archs for CPU-only builds

* Fix Qwen 3.5 MoE

* disable meta backend tests for WebGPU

* tests : filter CPU-based devices from the Meta backend tests (#17)

* meta : formatting, naming, indentation (#18)

* formatting : llama-model.cpp

* formatting : ggml-ext.h

* formatting : ggml-backend-meta.cpp

* meta : add TODO

* add documentation

* better error messages

* fix GPT-OSS

---------

Co-authored-by: Carl Philipp Klemm <carl@uvos.xyz>
Co-authored-by: Gaurav Garg <gaugarg@nvidia.com>
Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>
…org#21570)

Add AMD Instinct MI350X/MI355X (gfx950, CDNA4) support:

- vendors/hip.h: Add CDNA4 preprocessor define for __gfx950__
- common.cuh: Add GGML_CUDA_CC_CDNA4 and GGML_CUDA_CC_IS_CDNA4 macros
- mma.cuh: Route CDNA4 to compatible MFMA instructions:
  * f32 matmul: mfma_f32_16x16x4f32 (xf32 variant unavailable on gfx950)
  * bf16 matmul: mfma_f32_16x16x16bf16_1k (same as CDNA3)
  * int8 matmul: mfma_i32_16x16x32_i8/32x32x16 (same as CDNA3)
- mmq.cuh: Include CDNA4 in stream-k kernel dispatch

CDNA4 is largely compatible with CDNA3 except:
- No xf32 MFMA (mfma_f32_16x16x8_xf32) — routes to f32 path
- Different FP8 format (e4m3fn vs e4m3_fnuz) — not changed here

Tested on AMD Instinct MI355X (gfx950), ROCm 7.0.1:
- Build: compiles cleanly with -DAMDGPU_TARGETS=gfx950
- llama-bench (Qwen2.5-1.5B Q4_K_M, single GPU):
  * f16+FA: 40,013 tok/s prefill, 254 tok/s decode
  * q8_0+FA: functional
- Flash attention: works correctly
- MMQ: works correctly with stream-k dispatch

Co-authored-by: Andy Luo <andyluo7@users.noreply.github.com>
Signed-off-by: Adrien Gallouët <angt@huggingface.co>
* vulkan: Support Q1_0

* use get_dm
* fix: enable reasoning budget sampler for gemma4

Add thinking_start_tag and thinking_end_tag to
common_chat_params_init_gemma4(). Without these, the reasoning
budget sampler never activates for gemma4.

Make the newline after "thought" optional in the PEG parser to
handle budget=0 (sampler forces end tag before the newline).

Add test case for empty thinking block.

Fixes ggml-org#21487

* use p.space() instead of p.optional(p.literal("\n")) in gemma4 thought parser
* refactor: Build improvements

* chore: Formatting + package lock update
I'm not sure what the purpose of keeping `--alias` was when using
`--models-preset`, but the result is really weird, as shown in the
following logs:

    $ build/bin/llama-server --models-preset preset.ini --alias "Gemma 4 E4B UD Q8_K_XL"
    ...
    init: using 31 threads for HTTP server
    srv   load_models: Loaded 2 cached model presets
    srv   load_models: Loaded 1 custom model presets from preset.ini
    main: failed to initialize router models: alias 'Gemma 4 E4B UD Q8_K_XL' for model 'angt/test-split-model-stories260K:F32' conflicts with existing model name

So I propose to simply ignore `--alias` too in this case. With this
commit, the server starts in routing mode correctly.

Signed-off-by: Adrien Gallouët <angt@huggingface.co>
…agment (ggml-org#21521)

* ggml(webgpu): fix the busy-polls in Emscripten  in the waitAny after ggml-org#20618, and remove the busy webgpu log

* Merge with upstream

* Fix GET_ROWS packed integer NaN when using f16 as memory buffer in shader quants

* Update Unary wgsl EXP and EXPM1 for f16 stability

* Fix GET_ROWS IQ4_XS strcut for NaN f16 canonicalization

* Fix numerical percision for unary sqrt when working with f16

* Fix NaN canonicalization for packed integers using f16

* Update err threshold for binary div ops when using f16

* backend: Keep one Dawn/WebGPU instance alive for the lifetime of the static backend

* clean: uncomment existing code logs

* clean: clean the unncessary debug info

* Refactor and generalize dequant helpers

* Remove deprecated quant structs

* Refactor shader defines to reduce repetition

* Remove error override for F16 type

* fix: fix the accidential removal of the proper initialization of ctx

* clean: clean legacy and format code

* fix: did not modify tests ops

---------

Co-authored-by: Jeremy J. Hartmann <jeremy@mtion.tv>
TheTom and others added 4 commits April 20, 2026 08:45
The TurboFlash two-pass fused attention kernel produces garbage output
on M5 Max (Apple10/Metal4) for all turbo3 V configs. Disabling by
default routes turbo3 through the standard FA path which works correctly.

Users can opt-in with TURBO_FLASH=1 for testing/debugging.

No perf regression — standard FA path matches TurboFlash speed within
noise (~55-57 t/s tg128 for q8_0/turbo3 on M5 Max).

Co-Authored-By: tturney@psyguard.ai
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The legacy memory pool (ggml_cuda_pool_leg) retains peak-sized
allocations permanently. For quantized KV flash attention, the f16
dequant temp buffers (K_f16, V_f16) stay allocated in the pool after
use, consuming more VRAM than the KV compression saves. This causes
quantized KV (q8_0, q4_0) to OOM before f16 at equivalent context
lengths on HIP/ROCm where VMM is unavailable.

Root cause: ggml_cuda_pool_leg::free() stores buffers in buffer_pool[]
for reuse and never calls cudaFree. On CUDA with VMM the OS can
reclaim unused virtual memory. On HIP without VMM (all consumer RDNA
3/4 GPUs), the pool permanently consumes peak VRAM.

Fix: on HIP, allocate f16 temp buffers with cudaMalloc and free with
cudaFree (via RAII wrapper) instead of the pool. Memory is released
after the FA kernel completes via cudaStreamSynchronize.

Trade-off: one cudaStreamSynchronize per FA call (~5% overhead at 32K).

Impact: CUDA/Metal unaffected (#ifdef GGML_USE_HIP only).
Confirmed: gfx1100 (RX 7900 XT), gfx1201 (RX 9070 XT)
Fixes: ggml-org#22107
@TheTom TheTom force-pushed the fix/hip-fa-pool-retention branch from 30c3c23 to 0b05974 Compare April 20, 2026 14:15
@TheTom TheTom merged commit 57f6b93 into master Apr 20, 2026
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