# Overview of performance test suite For design of the tests, see https://grpc.io/docs/guides/benchmarking. This document contains documentation of on how to run gRPC end-to-end benchmarks using the gRPC OSS benchmarks framework (recommended) or how to run them manually (for experts only). ## Approach 1: Use gRPC OSS benchmarks framework (Recommended) ### gRPC OSS benchmarks The scripts in this section generate LoadTest configurations for the GKE-based gRPC OSS benchmarks framework. This framework is stored in a separate repository, [grpc/test-infra]. These scripts, together with tools defined in [grpc/test-infra], are used in the continuous integration setup defined in [grpc_e2e_performance_gke.sh] and [grpc_e2e_performance_gke_experiment.sh]. #### Generating scenarios The benchmarks framework uses the same test scenarios as the legacy one. The script [scenario_config_exporter.py](./scenario_config_exporter.py) can be used to export these scenarios to files, and also to count and analyze existing scenarios. The language(s) and category of the scenarios are of particular importance to the tests. Continuous runs will typically run tests in the `scalable` category. The following example counts scenarios in the `scalable` category: ``` $ ./tools/run_tests/performance/scenario_config_exporter.py --count_scenarios --category=scalable Scenario count for all languages (category: scalable): Count Language Client Server Categories 77 c++ scalable 19 python_asyncio scalable 16 java scalable 12 go scalable 12 node node scalable 12 node_purejs node scalable 9 csharp scalable 7 python scalable 5 ruby scalable 4 csharp c++ scalable 4 php7 c++ scalable 4 php7_protobuf_c c++ scalable 3 python_asyncio c++ scalable 2 ruby c++ scalable 2 python c++ scalable 1 csharp c++ scalable 189 total scenarios (category: scalable) ``` Client and server languages are only set for cross-language scenarios, where the client or server language do not match the scenario language. #### Generating load test configurations The benchmarks framework uses LoadTest resources configured by YAML files. Each LoadTest resource specifies a driver, a server, and one or more clients to run the test. Each test runs one scenario. The scenario configuration is embedded in the LoadTest configuration. Example configurations for various languages can be found here: https://github.com/grpc/test-infra/tree/master/config/samples The script [loadtest_config.py](./loadtest_config.py) generates LoadTest configurations for tests running a set of scenarios. The configurations are written in multipart YAML format, either to a file or to stdout. Each configuration contains a single embedded scenario. The LoadTest configurations are generated from a template. Any configuration can be used as a template, as long as it contains the languages required by the set of scenarios we intend to run (for instance, if we are generating configurations to run go scenarios, the template must contain a go client and a go server; if we are generating configurations for cross-language scenarios that need a go client and a C++ server, the template must also contain a C++ server; and the same for all other languages). The LoadTests specified in the script output all have unique names and can be run by applying the test to a cluster running the LoadTest controller with `kubectl apply`: ``` $ kubectl apply -f loadtest_config.yaml ``` > Note: The most common way of running tests generated by this script is to use > a _test runner_. For details, see [running tests](#running-tests). A basic template for generating tests in various languages can be found here: [loadtest_template_basic_all_languages.yaml](./templates/loadtest_template_basic_all_languages.yaml). The following example generates configurations for C# and Java tests using this template, including tests against C++ clients and servers, and running each test twice: ``` $ ./tools/run_tests/performance/loadtest_config.py -l go -l java \ -t ./tools/run_tests/performance/templates/loadtest_template_basic_all_languages.yaml \ -s client_pool=workers-8core -s driver_pool=drivers \ -s server_pool=workers-8core \ -s big_query_table=e2e_benchmarks.experimental_results \ -s timeout_seconds=3600 --category=scalable \ -d --allow_client_language=c++ --allow_server_language=c++ \ --runs_per_test=2 -o ./loadtest.yaml ``` The script `loadtest_config.py` takes the following options: - `-l`, `--language`
Language to benchmark. May be repeated. - `-t`, `--template`
Template file. A template is a configuration file that may contain multiple client and server configuration, and may also include substitution keys. - `-s`, `--substitution` Substitution keys, in the format `key=value`. These keys are substituted while processing the template. Environment variables that are set by the load test controller at runtime are ignored by default (`DRIVER_PORT`, `KILL_AFTER`, `POD_TIMEOUT`). The user can override this behavior by specifying these variables as keys. - `-p`, `--prefix`
Test names consist of a prefix_joined with a uuid with a dash. Test names are stored in `metadata.name`. The prefix is also added as the `prefix` label in `metadata.labels`. The prefix defaults to the user name if not set. - `-u`, `--uniquifier_element`
Uniquifier elements may be passed to the test to make the test name unique. This option may be repeated to add multiple elements. The uniquifier elements (plus a date string and a run index, if applicable) are joined with a dash to form a _uniquifier_. The test name uuid is derived from the scenario name and the uniquifier. The uniquifier is also added as the `uniquifier` annotation in `metadata.annotations`. - `-d`
This option is a shorthand for the addition of a date string as a uniquifier element. - `-a`, `--annotation`
Metadata annotation to be stored in `metadata.annotations`, in the form key=value. May be repeated. - `-r`, `--regex`
Regex to select scenarios to run. Each scenario is embedded in a LoadTest configuration containing a client and server of the language(s) required for the test. Defaults to `.*`, i.e., select all scenarios. - `--category`
Select scenarios of a specified _category_, or of all categories. Defaults to `all`. Continuous runs typically run tests in the `scalable` category. - `--allow_client_language`
Allows cross-language scenarios where the client is of a specified language, different from the scenario language. This is typically `c++`. This flag may be repeated. - `--allow_server_language`
Allows cross-language scenarios where the server is of a specified language, different from the scenario language. This is typically `node` or `c++`. This flag may be repeated. - `--instances_per_client`
This option generates multiple instances of the clients for each test. The instances are named with the name of the client combined with an index (or only an index, if no name is specified). If the template specifies more than one client for a given language, it must also specify unique names for each client. In the most common case, the template contains only one unnamed client for each language, and the instances will be named `0`, `1`, ... - `--runs_per_test`
This option specifies that each test should be repeated `n` times, where `n` is the value of the flag. If `n` > 1, the index of each test run is added as a uniquifier element for that run. - `-o`, `--output`
Output file name. The LoadTest configurations are added to this file, in multipart YAML format. Output is streamed to `sys.stdout` if not set. The script adds labels and annotations to the metadata of each LoadTest configuration: The following labels are added to `metadata.labels`: - `language`
The language of the LoadTest scenario. - `prefix`
The prefix used in `metadata.name`. The following annotations are added to `metadata.annotations`: - `scenario`
The name of the LoadTest scenario. - `uniquifier`
The uniquifier used to generate the LoadTest name, including the run index if applicable. [Labels](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/) can be used in selectors in resource queries. Adding the prefix, in particular, allows the user (or an automation script) to select the resources started from a given run of the config generator. [Annotations](https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/) contain additional information that is available to the user (or an automation script) but is not indexed and cannot be used to select objects. Scenario name and uniquifier are added to provide the elements of the LoadTest name uuid in human-readable form. Additional annotations may be added later for automation. #### Concatenating load test configurations The LoadTest configuration generator can process multiple languages at a time, assuming that they are supported by the template. The convenience script [loadtest_concat_yaml.py](./loadtest_concat_yaml.py) is provided to concatenate several YAML files into one, so configurations generated by multiple generator invocations can be concatenated into one and run with a single command. The script can be invoked as follows: ``` $ loadtest_concat_yaml.py -i infile1.yaml infile2.yaml -o outfile.yaml ``` #### Generating load test examples The script [loadtest_examples.sh](./loadtest_examples.sh) is provided to generate example load test configurations in all supported languages. This script takes only one argument, which is the output directory where the configurations will be created. The script produces a set of basic configurations, as well as a set of template configurations intended to be used with prebuilt images. The [examples](https://github.com/grpc/test-infra/tree/master/config/samples) in the repository [grpc/test-infra] are generated by this script. #### Generating configuration templates The script [loadtest_template.py](./loadtest_template.py) generates a load test configuration template from a set of load test configurations. The source files may be load test configurations or load test configuration templates. The generated template supports all languages supported in any of the input configurations or templates. The example template in [loadtest_template_basic_template_all_languages.yaml](./templates/loadtest_template_basic_all_languages.yaml) was generated from the example configurations in [grpc/test-infra] by the following command: ``` $ ./tools/run_tests/performance/loadtest_template.py \ -i ../test-infra/config/samples/*_example_loadtest.yaml \ --inject_client_pool --inject_server_pool \ --inject_big_query_table --inject_timeout_seconds \ -o ./tools/run_tests/performance/templates/loadtest_template_basic_all_languages.yaml \ --name basic_all_languages ``` The example template with prebuilt images in [loadtest_template_prebuilt_all_languages.yaml](./templates/loadtest_template_prebuilt_all_languages.yaml) was generated by the following command: ``` $ ./tools/run_tests/performance/loadtest_template.py \ -i ../test-infra/config/samples/templates/*_example_loadtest_with_prebuilt_workers.yaml \ --inject_client_pool --inject_driver_image --inject_driver_pool \ --inject_server_pool --inject_big_query_table --inject_timeout_seconds \ -o ./tools/run_tests/performance/templates/loadtest_template_prebuilt_all_languages.yaml \ --name prebuilt_all_languages ``` The script `loadtest_template.py` takes the following options: - `-i`, `--inputs`
Space-separated list of the names of input files containing LoadTest configurations. May be repeated. - `-o`, `--output`
Output file name. Outputs to `sys.stdout` if not set. - `--inject_client_pool`
If this option is set, the pool attribute of all clients in `spec.clients` is set to `${client_pool}`, for later substitution. - `--inject_driver_image`
If this option is set, the image attribute of the driver(s) in `spec.drivers` is set to `${driver_image}`, for later substitution. - `--inject_driver_pool`
If this attribute is set, the pool attribute of the driver(s) is set to `${driver_pool}`, for later substitution. - `--inject_server_pool`
If this option is set, the pool attribute of all servers in `spec.servers` is set to `${server_pool}`, for later substitution. - `--inject_big_query_table`
If this option is set, spec.results.bigQueryTable is set to `${big_query_table}`. - `--inject_timeout_seconds`
If this option is set, `spec.timeoutSeconds` is set to `${timeout_seconds}`. - `--inject_ttl_seconds`
If this option is set, `spec.ttlSeconds` is set to `${ttl_seconds}`. - `-n`, `--name`
Name to be set in `metadata.name`. - `-a`, `--annotation`
Metadata annotation to be stored in `metadata.annotations`, in the form key=value. May be repeated. The options that inject substitution keys are the most useful for template reuse. When running tests on different node pools, it becomes necessary to set the pool, and usually also to store the data on a different table. When running as part of a larger collection of tests, it may also be necessary to adjust test timeout and time-to-live, to ensure that all tests have time to complete. The template name is replaced again by `loadtest_config.py`, and so is set only as a human-readable memo. Annotations, on the other hand, are passed on to the test configurations, and may be set to values or to substitution keys in themselves, allowing future automation scripts to process the tests generated from these configurations in different ways. #### Running tests Collections of tests generated by `loadtest_config.py` are intended to be run with a test runner. The code for the test runner is stored in a separate repository, [grpc/test-infra]. The test runner applies the tests to the cluster, and monitors the tests for completion while they are running. The test runner can also be set up to run collections of tests in parallel on separate node pools, and to limit the number of tests running in parallel on each pool. For more information, see the [tools README](https://github.com/grpc/test-infra/blob/master/tools/README.md) in [grpc/test-infra]. For usage examples, see the continuous integration setup defined in [grpc_e2e_performance_gke.sh] and [grpc_e2e_performance_gke_experiment.sh]. [grpc/test-infra]: https://github.com/grpc/test-infra [grpc_e2e_performance_gke.sh]: ../../internal_ci/linux/grpc_e2e_performance_gke.sh [grpc_e2e_performance_gke_experiment.sh]: ../../internal_ci/linux/grpc_e2e_performance_gke_experiment.sh ## Approach 2: Running benchmarks locally via legacy tooling (still useful sometimes) This approach is much more involved than using the gRPC OSS benchmarks framework (see above), but can still be useful for hands-on low-level experiments (especially when you know what you are doing). ### Prerequisites for running benchmarks manually: In general the benchmark workers and driver build scripts expect [linux_performance_worker_init.sh](../../gce/linux_performance_worker_init.sh) to have been ran already. ### To run benchmarks locally: - From the grpc repo root, start the [run_performance_tests.py](../run_performance_tests.py) runner script. ### On remote machines, to start the driver and workers manually: The [run_performance_test.py](../run_performance_tests.py) top-level runner script can also be used with remote machines, but for e.g., profiling the server, it might be useful to run workers manually. 1. You'll need a "driver" and separate "worker" machines. For example, you might use one GCE "driver" machine and 3 other GCE "worker" machines that are in the same zone. 2. Connect to each worker machine and start up a benchmark worker with a "driver_port". - For example, to start the grpc-go benchmark worker: [grpc-go worker main.go](https://github.com/grpc/grpc-go/blob/master/benchmark/worker/main.go) --driver_port #### Commands to start workers in different languages: - Note that these commands are what the top-level [run_performance_test.py](../run_performance_tests.py) script uses to build and run different workers through the [build_performance.sh](./build_performance.sh) script and "run worker" scripts (such as the [run_worker_java.sh](./run_worker_java.sh)). ##### Running benchmark workers for C-core wrapped languages (C++, Python, C#, Node, Ruby): - These are more simple since they all live in the main grpc repo. ``` $ cd $ tools/run_tests/performance/build_performance.sh $ tools/run_tests/performance/run_worker_.sh ``` - Note that there is one "run_worker" script per language, e.g., [run_worker_csharp.sh](./run_worker_csharp.sh) for c#. ##### Running benchmark workers for gRPC-Java: - You'll need the [grpc-java](https://github.com/grpc/grpc-java) repo. ``` $ cd $ ./gradlew -PskipCodegen=true -PskipAndroid=true :grpc-benchmarks:installDist $ benchmarks/build/install/grpc-benchmarks/bin/benchmark_worker --driver_port ``` ##### Running benchmark workers for gRPC-Go: - You'll need the [grpc-go repo](https://github.com/grpc/grpc-go) ``` $ cd /benchmark/worker && go install $ # if profiling, it might be helpful to turn off inlining by building with "-gcflags=-l" $ $GOPATH/bin/worker --driver_port ``` #### Build the driver: - Connect to the driver machine (if using a remote driver) and from the grpc repo root: ``` $ tools/run_tests/performance/build_performance.sh ``` #### Run the driver: 1. Get the 'scenario_json' relevant for the scenario to run. Note that "scenario json" configs are generated from [scenario_config.py](./scenario_config.py). The [driver](../../../test/cpp/qps/qps_json_driver.cc) takes a list of these configs as a json string of the form: `{scenario: }` in its `--scenarios_json` command argument. One quick way to get a valid json string to pass to the driver is by running the [run_performance_tests.py](./run_performance_tests.py) locally and copying the logged scenario json command arg. 2. From the grpc repo root: - Set `QPS_WORKERS` environment variable to a comma separated list of worker machines. Note that the driver will start the "benchmark server" on the first entry in the list, and the rest will be told to run as clients against the benchmark server. Example running and profiling of go benchmark server: ``` $ export QPS_WORKERS=:<10000>,,10000,:10000 $ bins/opt/qps_json_driver --scenario_json='' ``` ### Example profiling commands While running the benchmark, a profiler can be attached to the server. Example to count syscalls in grpc-go server during a benchmark: - Connect to server machine and run: ``` $ netstat -tulpn | grep # to get pid of worker $ perf stat -p -e syscalls:sys_enter_write # stop after test complete ``` Example memory profile of grpc-go server, with `go tools pprof`: - After a run is done on the server, see its alloc profile with: ``` $ go tool pprof --text --alloc_space http://localhost:/debug/heap ``` ### Configuration environment variables: - QPS_WORKER_CHANNEL_CONNECT_TIMEOUT Consuming process: qps_worker Type: integer (number of seconds) This can be used to configure the amount of time that benchmark clients wait for channels to the benchmark server to become ready. This is useful in certain benchmark environments in which the server can take a long time to become ready. Note: if setting this to a high value, then the scenario config under test should probably also have a large "warmup_seconds". - QPS_WORKERS Consuming process: qps_json_driver Type: comma separated list of host:port Set this to a comma separated list of QPS worker processes/machines. Each scenario in a scenario config has specifies a certain number of servers, `num_servers`, and the driver will start "benchmark servers"'s on the first `num_server` `host:port` pairs in the comma separated list. The rest will be told to run as clients against the benchmark server.