Forums - CPU fallback forcing all layers to run on CPU

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CPU fallback forcing all layers to run on CPU
Join Date: 24 Feb 20
Posts: 6
Posted: Tue, 2021-07-13 20:56

Dear Sir,

Application used: snpe-net-run and Native CPP standalone(snpe-sample)

SNPE version: 1.52

Target device: Qualcomm SA6155P

We had a model which was running on CPU and DSP successfully.

We added DSP non-supported layer to the same model to test the CPU_FALLBACK feature as per our requirement we were expecting the non-supported layer to run on CPU and rest model should run on DSP as it was running earlier.


a) The whole model fallsback to CPU and all layers were running on CPU only.

logs for your reference:

Native Cpp Application:

root@sa6155:/data/local/tmp/vyom/cpu_fall_back_test_3# /data/local/tmp/vyom/cpu_fall_back_test_2/snpe-sample -b ITENSOR -d /data/local/tmp/vyom/cpu_fall_back_test_3/avod_part2_quant_bc_cropResize_bev2.dlc
  -i /data/local/tmp/vyom/cpu_fall_back_test_3/input_part2_cropResize_bev_1.txt  -o output -r dsp
SNPE Version:
Selected runtime not present. Falling back to CPU.

Processing DNN Input:
        1) /data/local/tmp/vyom/cpu_fall_back_test_3/proposals_reshape_nms.raw
        2) bev_vgg_pyr_strided_slice.raw
        3) avod_roi_pooling_Reshape.raw
Finished processing inputs for current inference


snpe-net-run Application logs:

root@sa6155:/data/local/tmp/vyom/cpu_fall_back_test_3# snpe-net-run --input_list /data/local/tmp/vyom/cpu_fall_back_test_3/input_part2_cropResize_bev.txt  --container /data/local/tmp/vyom/cpu_fall_back_te

st_3/avod_part2_quant_bc_cropResize_bev2.dlc  --output_dir output --use_dsp --enable_cpu_fallback

The selected runtime is not available on this platform. Continue anyway to observe the failure at network creation time.
Model String: N/A
SNPE v1.52.0.2724
Processing DNN input(s):
Processing DNN input(s):
Processing DNN input(s):




Note: This application is Native Cpp SNPE standlaone where we have set the CPU fallback functionality in SNPEBuilder options. Same behaviour is observed with snpe-net-run also.


What could be the possible reason for this behaviour, how to resolve the same.


Thanks and Regards,

Vyom Mishra

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Join Date: 29 May 18
Posts: 33
Posted: Tue, 2021-08-24 20:29


Can you please try -- use-aip option. This seems to automatically distribute layers on supported runtimes. Please see the documentation here:



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