Files
llama.cpp-xrip/tools/server/tests
Leebr Data ConsultingandIgor Okulist 033df86b69 server : preserve context checkpoints across slot save/restore (#26004)
* server : preserve context checkpoints across slot save/restore

Append the checkpoints after the packed server_tokens payload added in #26640
and count them in n_written / n_read, so a restored slot can still roll back to
a checkpoint instead of re-processing the whole prompt.

* server : drop draft checkpoint data that does not match the draft context

Restoring a slot saved with a different draft KV cache type aborted in
load_dft(). Test-load one draft checkpoint on restore and drop the draft
data if it does not fit, instead of crashing. Adds a regression test.

Co-authored-by: Igor Okulist <okigan@gmail.com>

* server : harden the checkpoint appendix of slot save files

Bound each blob size by the bytes left in the file before allocating, open the
file with UTF-8 paths on Windows like the llama state payload, fall back to full
prompt re-processing when a checkpoint restored from a slot file fails to load,
and replace the 1024 count cap by keeping the last n_ctx_checkpoints while reading.

* server : report an incomplete checkpoint appendix as a failed slot save

Return an error to the client when the appendix cannot be written, like a
failed payload write, and make the oversized-blob test declare a size that
cannot be allocated, so an unbounded allocation fails the test.

* server : reject an empty target state in the checkpoint appendix

A saved checkpoint always holds a target state, an empty blob would roll back
without restoring anything. Also log with the slot id, and load the draft test
model from the HF cache instead of a second download.

* common : return bool from checkpoint load_tgt / load_dft

A checkpoint restored from a slot file falls back to full prompt re-processing
when it fails to load, a checkpoint created in memory still aborts.

---------

Co-authored-by: Igor Okulist <okigan@gmail.com>
2026-10-08 13:18:20 +03:00
..

Server tests

Python based server tests scenario using pytest.

Tests target GitHub workflows job runners with 4 vCPU.

Note: If the host architecture inference speed is faster than GitHub runners one, parallel scenario may randomly fail. To mitigate it, you can increase values in n_predict, kv_size.

Install dependencies

pip install -r requirements.txt

Run tests

  1. Build the server
cd ../../..
cmake -B build
cmake --build build --target llama-server
  1. Start the test: ./tests.sh

It's possible to override some scenario steps values with environment variables:

variable description
PORT context.server_port to set the listening port of the server during scenario, default: 8080
LLAMA_SERVER_BIN_PATH to change the server binary path, default: ../../../build/bin/llama-server
DEBUG to enable steps and server verbose mode --verbose
N_GPU_LAYERS number of model layers to offload to VRAM -ngl --n-gpu-layers
LLAMA_CACHE by default server tests re-download models to the tmp subfolder. Set this to your cache (e.g. $HOME/Library/Caches/llama.cpp on Mac or $HOME/.cache/llama.cpp on Unix) to avoid this

To run slow tests (will download many models, make sure to set LLAMA_CACHE if needed):

SLOW_TESTS=1 ./tests.sh

To run with stdout/stderr display in real time (verbose output, but useful for debugging):

DEBUG=1 ./tests.sh -s -v -x

To run all the tests in a file:

./tests.sh unit/test_chat_completion.py -v -x

To run a single test:

./tests.sh unit/test_chat_completion.py::test_invalid_chat_completion_req

Hint: You can compile and run test in single command, useful for local development:

cmake --build build -j --target llama-server && ./tools/server/tests/tests.sh

To see all available arguments, please refer to pytest documentation

Debugging external llama-server

It can sometimes be useful to run the server in a debugger when invesigating test failures. To do this, the environment variable DEBUG_EXTERNAL=1 can be set which will cause the test to skip starting a llama-server itself. Instead, the server can be started in a debugger.

Example using gdb:

$ gdb --args ../../../build/bin/llama-server \
    --host 127.0.0.1 --port 8080 \
    --temp 0.8 --seed 42 \
    --hf-repo ggml-org/models --hf-file tinyllamas/stories260K.gguf \
    --batch-size 32 --no-slots --alias tinyllama-2 --ctx-size 512 \
    --parallel 2 --n-predict 64

And a break point can be set in before running:

(gdb) br server.cpp:4604
(gdb) r
main: server is listening on http://127.0.0.1:8080 - starting the main loop
srv  update_slots: all slots are idle

And then the test in question can be run in another terminal:

(venv) $ env DEBUG_EXTERNAL=1 ./tests.sh unit/test_chat_completion.py -v -x

And this should trigger the breakpoint and allow inspection of the server state in the debugger terminal.