Connectivity Serdes Test Plugins Design, Switches and Parameters

This section describes plugin specific switches only. Common plugin switches and parameters are described in hl_qual Common Plugin Switches and Parameters.

Serdes Base Test Design Consideration and Responsibilities

The Serdes base test performs basic sanity tests on the Serdes, ensuring the following parts are tested:

• Internal and external port connectivity.

• RX/TX data integrity - Checked by pre-calculated random data and compared against a reference data. The default transmitted buffer size is 128MB to ensure a variety of transmitted data. During the test, the TX buffer is transmitted multiple times according to the test execution time set.

Serdes Base Test Testing Modes

The test plugin consists of the below sub-testing modes:

Gaudi 3 and Gaudi 2

• pairs - Runs over all available device pairs and tests the internal port connectivity. In this mode, the test runs a data integrity test on each pair of devices.

• allgather - Runs over all available devices and computes the bandwidth of allgather functionality.

• allreduce - Runs over all available devices and computes the bandwidth of allreduce functionality.

• loopback - Runs over all available devices and tests the external ports connectivity. In this mode, the external ports must be fitted with loopback dongles. Calculates only bandwidth.

• dir_bw (direct bandwidth) - Runs over all available devices. In each iteration one device is a sender and the rest are receivers. Calculates only bandwidth.

The allgather and allreduce variants also calculate the bandwidth for those network operations. You may run the test for a specific number of epochs and iterations per epoch using the -i switch. This generates a MAX, MIN and average bandwidth per epoch which may expose bandwidth instabilities to the time duration of the test.

Note

allgather, allreduce, loopback, and dir_bw variants calculate the bandwidth for NIC port integrity only. They do not validate NIC port integrity.

First-gen Gaudi

• pairs - Runs over all available device pairs and tests the internal port connectivity. In this mode, the test runs a data integrity test on each pair of devices.

• allgather - Runs over all available devices and computes the bandwidth of allgather functionality.

• allreduce - Runs over all available devices and computes the bandwidth of allreduce functionality.

The allgather and allreduce variants also calculate the bandwidth for those network operations. You may run the test for a specific number of epochs and iterations per epoch using the -i switch. This generates a MAX, MIN and average bandwidth per epoch which may expose bandwidth instabilities to the time duration of the test.

Note

Both allgather and allreduce variants calculate the bandwidth for NIC port integrity only. They do not validate NIC port integrity.

Serdes Base - Pass/Fail Criteria

The pass/fail criteria consists of two sub-criteria:

• The test fails if the destination rank does not respond.

• The test fails if data is not received as expected compared with the reference data.

Serdes Base Test Plugin Switches and Parameters

Gaudi 3

hl_qual -gaudi3 -c <pci bus id> [-i <inner loop iterations count>] [-ep <epoch count>] -rmod <serial | parallel>  [-dis_mon] [-mon_cfg <monitor INI path>]
-nic_base -test_type <pairs | allreduce | allgather | loopback | dir_bw> [-sz <size in bytes>] [-seed <seed>]

Switches and Parameters	Description
-test_type <test type>	Defines the test type and port configuration to be used in your system. The different test type variants are: pairs - Checks the internal port connectivity. allgather - Computes the allgather bandwidth. allreduce - Computes the allreduce bandwidth. loopback - Checks the external port connectivity. dir_bw - Computes direct bandwidth.
-nic_base	Serdes base test selector.
-sz	Send/receive buffer size in bytes.
-i	Iteration count for bandwidth computation.
-ep	Epoch count for bandwidth computation. Note: This switch enables multiple epochs that consist of iterations. You can change the number of iterations using the -i switch. The -ep switch is applicable only for allgather and allreduce test modes.
--seed <seed>	Seed value for generating the transmit patterns. This is a 32 bit number with the following hexadecimal pattern xxxxxxxx (for example, abc123da). The default pattern is 5a5a5a5a5a.

./hl_qual -gaudi3 -c all -rmod parallel -i 50 -nic_base -test_type pairs
./hl_qual -gaudi3 -c all -rmod parallel -i 50 -ep 100 -nic_base -test_type allreduce

Gaudi 2

hl_qual -gaudi2 -c <pci bus id> [-i <inner loop iterations count>] [-ep <epoch count>] -rmod <serial | parallel> [-dis_mon] [-mon_cfg <monitor INI path>]
-nic_base -test_type <pairs | allreduce | allgather | loopback | dir_bw> [-sz <size in bytes>] [-disable_ports <port list>] [-seed <seed>] [-enable_ports_check <int | all>]

Switches and Parameters	Description
-test_type <test type>	Defines the test type and port configuration to be used in your system. The different test type variants are: pairs - Checks the internal port connectivity. allgather - Computes the allgather bandwidth. allreduce - Computes the allreduce bandwidth. loopback - Checks the external port connectivity. dir_bw - Computes direct bandwidth.
-nic_base	Serdes base test selector.
-sz	Send/receive buffer size in bytes.
-i	Iteration count for bandwidth computation.
-ep	Epoch count for bandwidth computation. Note: This switch enables multiple epochs that consist of iterations. You can change the number of iterations using the -i switch. The -ep switch is applicable only for allgather and allreduce test modes.
--seed <seed>	Seed value for generating the transmit patterns. This is a 32 bit number with the following hexadecimal pattern xxxxxxxx (for example, abc123da). The default pattern is 5a5a5a5a5a.
disable_ports	Specifies which ports to disable. For example, -disable_ports [1,2,3].
-enable_ports_check <all / int>	Indicates whether the ports are UP or DOWN. If the ports are DOWN, the test fails: all - Checks all the external and internal ports. int - Checks the internal ports only.

./hl_qual -gaudi2 -c all -rmod parallel -i 50 -nic_base -test_type pairs
./hl_qual -gaudi2 -c all -rmod parallel -i 50 -ep 100 -nic_base -test_type allreduce

First-gen Gaudi

hl_qual -gaudi -c <pci bus id> [-i <inner loop iterations count>] [-ep <epoch count>] -rmod <serial | parallel> [-dis_mon] [-mon_cfg <monitor INI path>]
-nic_base -test_type <pairs | allreduce | allgather> [-sz <size in bytes>] [-disable_ports <port list>] [-seed <seed>] [-enable_ports_check <int | all>]

Switches and Parameters	Description
-test_type <test type>	Defines the test type and port configuration to be used in your system. The different test type variants are: pairs - Checks the internal port connectivity. allgather - Computes the allgather bandwidth. allreduce - Computes the allreduce bandwidth.
-nic_base	Serdes base test selector.
-sz	Send/receive buffer size in bytes.
-i	Iteration count for bandwidth computation.
-ep	Epoch count for bandwidth computation. Note: This switch enables multiple epochs that consist of iterations. You can change the number of iterations using the -i switch. The -ep switch is applicable only for allgather and allreduce test modes.
--seed <seed>	Seed value for generating the transmit patterns. This is a 32 bit number with the following hexadecimal pattern xxxxxxxx (for example, abc123da). The default pattern is 5a5a5a5a5a.
disable_ports	Specifies which ports to disable. For example, -disable_ports [1,2,3].
-enable_ports_check <all / int>	Indicates whether the ports are UP or DOWN. If the ports are DOWN, the test fails: all - Checks all the external and internal ports. int - Checks the internal ports only.

./hl_qual -gaudi -c all -rmod parallel -i 20 -nic_base -test_type pairs
./hl_qual -gaudi -c all -rmod parallel -i 20 -ep 20 -nic_base -test_type allreduce

Gaudi 3/2 E2E Concurrency Test Plugin Design Consideration and Responsibilities

The E2E concurrency test plugin is a network bandwidth measurement test which calculates bandwidth per port and verifies transmission integrity. Since all verification processes run per port, you can identify port connectivity issues very easily. The test verifies all ports and provides calculated bandwidth per port, which offers testing benefits compared to the Serdes Base test which tests port pairs.

Note

(Gaudi 3) The E2E concurrency test is a low-level test that uses a special mode that ensures low latency and fast execution. This mode does not leave a trace on the utilization calculation when running the hl-smi tool. The tool outputs 0% utilization.

E2E Concurrency Test - Pass/Fail Criteria

The pass/fail criteria depends on the calculated bandwidth and correctness. The criteria is:

• Gaudi 3 - 190Gbps

• Gaudi 2 - 97Gbps

Gaudi 3/2 E2E Concurrency Test Plugin Switches and Parameters

Gaudi 3

hl_qual -gaudi3 -c <pci bus id> -rmod <parallel> [-t <execution time in seconds>] [-dis_mon] [-mon_cfg <monitor INI path>] -e2e_concurrency [-disable_detect_externals]

Switches and Parameters	Description
-e2e_concurrency	Test selector
-t	Power stress test duration in seconds.
-enable_externals	Enables external ports checking.

./hl_qual -gaudi3 -c all -rmod parallel -dis_mon -e2e_concurrency
./hl_qual -gaudi3 -c all -rmod parallel -t 30 -dis_mon -e2e_concurrency

Gaudi 2

hl_qual -gaudi2 -c <pci bus id> -rmod <parallel> [-t <execution time in seconds>] [-dis_mon] [-mon_cfg <monitor INI path>] -e2e_concurrency [-disable_ports] [-enable_ports_check <all | int>]

Switches and Parameters	Description
-e2e_concurrency	Test selector
-t	Power stress test duration in seconds.
-disable_ports	Specifies which ports to disable. For example, -disable_ports [1,2,3].
-enable_ports_check <int | all>	Indicates whether the ports are UP or DOWN. If the ports are DOWN, the test fails: all - Checks all the external and internal ports. int - Checks the internal ports only.

./hl_qual -gaudi2 -c all -rmod parallel -dis_mon -e2e_concurrency
./hl_qual -gaudi2 -c all -rmod parallel -t 30 -dis_mon -e2e_concurrency -disable_ports 8,22,23 -enable_ports_check int

First-gen Gaudi E2E Serdes Test Plugin Design Consideration and Responsibilities

The E2E Serdes test is a multi-purpose test that can check any machine topology using a connectivity JSON file. The file describes the machine’s unique connectivity and verifies both connectivity and bandwidth. The test runs on multiple Gaudi cards, testing the ports simultaneously to report the collective bandwidth.

Note

To use your own port connectivity configuration, contact Intel Gaudi support.

E2E Serdes Test Testing Modes

• external-lpbk- A Serdes loopback communication test. This testing mode runs on all external ports of the NICs and sends data through a loopback dongle from each external port back to itself. When running this test mode, the external ports must be connected (RX to TX) using a loopback dongle.

• internal - This mode sends data from each internal port to its connected port on a different first-gen Gaudi device.

• all-lpbk - This mode runs the plugin on all internal and external ports simultaneously. The test of the external ports is loopback so all external ports must be connected (RX to TX) using a loopback dongle.

E2E Serdes Test- Pass/Fail Criteria

The pass/fail criteria consists of the following:

• There is an E2E connection between ports.

• There is no loopback.

• The collective bandwidth is printed at the end of the test.

• When the test runs in Sanity mode using the -executeSanity flag, it fails if the bit error exceeds 0.1%.

First-gen Gaudi E2E Serdes Test Plugin Switches and Parameters

sudo hl_qual -gaudi -e2e -port_map <json name> -test_mode <all-lpbk | internal | external-lpbk> -c <pci bus id> -rmod <serial | parallel> [-dis_mon] [-mon_cfg <monitor INI path>] [-enable_ports_check <all | int>]

Switches and Parameters	Description
-e2e	Serdes base test selector.
-port_map <name of json configuration file>	A JSON file that defines the ports connectivity within the server box and which ports are external.
-test_mode <test type>	Defines the test type and port configuration to be used in your system. The different test type variants are: all-lpbk - Executes both internal and external tests. This mode only runs with -rmod parallel. internal - Checks the internal port connectivity. This mode only runs with -rmod parallel. external-lpbk - Tests all external ports and assumes loopback dongle on all external ports.
-enable_ports_check <all / int>	Indicates whether the ports are UP or DOWN. If the ports are DOWN, the test fails: all - Checks all the external and internal ports. int - Checks the internal ports only.

The below command runs the E2E test on both external ports with loopback dongles and internal ports. The network topology is defined by hls1.json:

sudo ./hl_qual -c all -test_mode all-lpbk -rmod parallel -e2e -port_map hls1.json -gaudi

Gaudi 3/2 SER Test Plugin Design Consideration and Responsibilities

The SER test plugin is a Symbol Error Rate measurement test which calculates pre and post FEC SER for each port.

The SER test execution time could be lengthy and depends on the state of the Intel Gaudi Linux kernel driver. During this test, the devices undergo hard resets to perform various stages of the test. The test plugin needs to wait for the device to reach a stable state of operation after each hard reset.

In Gaudi 2, you can check Bit Error Rate (BER) measurement using -ber_enable switch. The BER test calculates the port and lane bit error rate.

Note

(Gaudi 3) The SER test is a low-level test that uses a special mode that ensures low latency and fast execution. This mode does not leave a trace on the utilization calculation when running the hl-smi tool. The tool outputs 0% utilization.

SER Test - Pass/Fail Criteria

The pass/fail criteria depends on the calculated post FEC SER. The SER plugin pass/fail criteria for this mode is 1.0E-6.

Gaudi 3/2 SER Test Plugin Switches and Parameters

Gaudi 3

hl_qual -gaudi3 -c <pci bus id> -rmod <serial | parallel> [-dis_mon] [-mon_cfg <monitor INI path>] -ser [-enable_ext]

Switches and Parameters	Description
-ser	SER test selector.
-enable_ext	Enables external ports checking.

./hl_qual -gaudi3 -c all -rmod parallel -dis_mon -ser
./hl_qual -gaudi3 -c all -rmod parallel -ser -enable_ext

Gaudi 2

hl_qual -gaudi2 -c <pci bus id> -rmod <serial | parallel> [-dis_mon] [-mon_cfg <monitor INI path>] -ser [-enable_ext] [-ber_enable]

Switches and Parameters	Description
-ser	SER test selector.
-ber_enable	Enables BER check.
-enable_ext	Enables external ports checking.

./hl_qual -gaudi2 -c all -rmod parallel -dis_mon -ser
./hl_qual -gaudi2 -c all -rmod parallel -ser -enable_ext