DPDK, OAI and kernel threads require to be properly allocated to extract maximum real-time performance for your use case.
1.**NOTE**: Currently the default OAI 7.2 configuration file requires isolated **CPUs 0,2,4** for DPDK/libXRAN, **CPU 6** for `ru_thread` and **CPU 8** for `L1_rx_thread`. It is preferrable to have all these threads on the same socket.
1.**NOTE**: Currently the default OAI 7.2 configuration file requires isolated **CPUs 0,2,4** for DPDK/libXRAN, **CPU 6** for `ru_thread`, **CPU 8** for `L1_rx_thread` and **CPU 10** for `L1_tx_thread`. It is preferrable to have all these threads on the same socket.
2. Allocating CPUs to the OAI nr-softmodem is done using the `--thread-pool` option. Allocating 4 CPUs is the minimal configuration but we recommend to allocate at least **8** CPUs. And they can be on a different socket as the DPDK threads.
3. And to avoid kernel preempting these allocated CPUs, it is better to force the kernel to use un-allocated CPUs.
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@@ -102,6 +102,7 @@ Let summarize for example on a `32-CPU` single NUMA node system, regardless of t
|XRAN DPDK usage |0,2,4 |
|OAI `ru_thread` |6 |
|OAI `L1_rx_thread` |8 |
|OAI `L1_tx_thread` |10 |
|OAI `nr-softmodem` |1,3,5,7,9,11,13,15|
|kernel |16-31 |
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@@ -602,6 +603,7 @@ Edit the sample OAI gNB configuration file and check following parameters:
*`L1s` section
* Set an isolated core for L1 thread `L1_rx_thread_core`, in our environment we are using CPU 8
* Set an isolated core for L1 thread `L1_tx_thread_core`, in our environment we are using CPU 10
*`phase_compensation` should be set to 0 to disable when it is performed in the RU and set to 1 when it should be performed on the DU side
