Update benchmarks doc to list all current tests

docs/benchmarks.md

@@ -17,9 +17,83 @@ We run two types of automated benchmark tests for Phase 2:
   Benchmarks](https://open-telemetry.github.io/otel-arrow/benchmarks/nightly/)**
   - Comprehensive test suites run nightly
 
-Both provide performance metrics for the OTAP dataflow engine, for various
-scenarios.
-<!-- TODO: Add details on the scenario -->
+Both provide performance metrics for the OTAP dataflow engine for various
+scenarios. Unless otherwise specified, all tests run on a single CPU core.
+
+#### 1. Filter + OTel Collector Comparison
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/nightly/filter/>
+
+Tests a filter scenario where a filter processor drops 95% of logs. Processes
+approximately 100k logs/sec input with ~5k logs/sec output. The benchmark page
+includes a direct comparison with the equivalent OTel Collector performing the
+same filtering operation.
+
+#### 2. Backpressure
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/nightly/backpressure/>
+
+Measures backpressure impact with `wait_for_result` set to true on the dataflow
+engine receivers. Processes approximately 100k logs/sec input and output. The
+pipeline includes an attribute processor configured to rename an attribute,
+which forces the dataflow engine to perform in-memory representation and
+conversion rather than operating in pass-through mode.
+
+#### 3. Syslog
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/nightly/syslog/>
+
+Tests syslog ingestion via UDP with two variations:
+
+- Basic syslog message format
+- CEF (Common Event Format) formatted messages
+
+Processes approximately 5k logs/sec input and output.
+
+#### 4. Normal Load
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/continuous/>
+
+Standard load test processing 100k records/sec input and output on a single CPU
+core. This test runs with each commit to main.
+
+#### 5. Saturation and Scaling
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/continuous-saturation/>
+
+Tests performance at saturation across different CPU configurations: 1, 2, 4, 8,
+and 16 cores.
+
+*TODO: Update test output to include scalability ratios in addition to raw
+throughput numbers.*
+
+#### 6. Idle State
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/continuous-idle-state/>
+
+Measures resource consumption in idle state with two variations:
+
+- Single core configuration
+- All-cores configuration (128 cores)
+
+#### 7. Binary Size
+
+**URL:** <https://open-telemetry.github.io/otel-arrow/benchmarks/binary-size/>
+
+Tracks the binary size of the dataflow engine for Linux ARM64 and AMD64
+architectures over time.
+
+### Metrics Collected
+
+All benchmark tests measure the following metrics:
+
+- **Logs/sec input** - Input throughput
+- **Logs/sec output** - Output throughput
+- **RAM** - Average and maximum memory usage
+- **Normalized CPU** - Average and maximum CPU usage, normalized to 0-100% where
+  100% represents full utilization of all available cores. For example, in a
+  4-core test, 80% means 3.2 cores are being used (0.8 X 4 cores)
+- **Network bytes/sec** - Input and output network bandwidth
 
 ### Learn More About Phase 2