Segmentation fault in PreSolve(), when initializing solver

[fiorato...@gmail.com]

Good morning everyone,

I have this issue when solver object is initialized and so the function PreSolve() is called. Below there is the error report with gdb.

I have some doubts on how the leveldb is created. So i put down here the code that i used to create the database:

int main(int argc, char** argv) {

    if (argc != 7){

        cout<<"option: name nData mean0 str0 mean1 str1"<<endl;

        return 0;

    }

    int dim = 2;

    const char* path = argv[1];

    int nData = atoi(argv[2]);

    Dtype mean_0 = atof(argv[3]);

    Dtype str_0 = atof(argv[4]);

    Dtype mean_1 = atof(argv[5]);

    Dtype str_1 = atof(argv[6]);

    // generate data from two 2-d gaussians

    Blob<Dtype>* const blob_data = new Blob<Dtype>(nData, dim, 1, 1);

    caffe_rng_gaussian<Dtype>(nData/2*dim, mean_0, str_0, blob_data->mutable_cpu_data());

    caffe_rng_gaussian<Dtype>(nData/2*dim, mean_1, str_1, blob_data->mutable_cpu_data()+blob_data->offset(nData/2,0,0,0));

    // open leveldb

    leveldb::DB* db;

    leveldb::Options options;

    options.error_if_exists = true;

    options.create_if_missing = true;

    options.write_buffer_size = 268435456;

    leveldb::WriteBatch* batch = NULL;

    leveldb::Status status = leveldb::DB::Open(options, path, &db);

    CHECK(status.ok()) << "Failed to open leveldb " << path

                       << ". Is it already existing?";

    batch = new leveldb::WriteBatch();

    // save to db

    const int kMaxKeyLength = 10;

    char key_cstr[kMaxKeyLength];

    leveldb::WriteOptions writeOptions;

    for (int item_id = 0; item_id < nData; ++item_id) {

        Datum datum;

        datum.set_channels(dim);

        datum.set_height(1);

        datum.set_width(1);

        datum.mutable_float_data()->Reserve(dim);

        for(int k=0;k<2;k++){

            datum.add_float_data(blob_data->cpu_data()[blob_data->offset(item_id,k,0,0)]);

        }

        if(item_id < nData/2)  datum.set_label(0);

        else datum.set_label(1);

        snprintf(key_cstr, kMaxKeyLength, "%08d", item_id);

        string keystr(key_cstr);

        db->Put(writeOptions, keystr, datum.SerializeAsString());

    }

    db->Write(leveldb::WriteOptions(), batch);

    delete batch;

    delete db;

    return 0;

}

And here is the error report:

I1106 15:01:45.541523 13838 layer_factory.hpp:77] Creating layer data

I1106 15:01:45.705741 13838 db_leveldb.cpp:18] Opened leveldb train_leveldb

I1106 15:01:45.706275 13838 net.cpp:84] Creating Layer data

I1106 15:01:45.706341 13838 net.cpp:380] data -> data

I1106 15:01:45.706445 13838 net.cpp:380] data -> label

I1106 15:01:45.706585 13838 data_layer.cpp:45] output data size: 200,2,1,1

[New Thread 0x7fffdc8fc700 (LWP 13847)]

I1106 15:01:45.707495 13838 net.cpp:122] Setting up data

I1106 15:01:45.707568 13838 net.cpp:129] Top shape: 200 2 1 1 (400)

I1106 15:01:45.707590 13838 net.cpp:129] Top shape: 200 (200)

I1106 15:01:45.707633 13838 net.cpp:137] Memory required for data: 4800

I1106 15:01:45.707659 13838 layer_factory.hpp:77] Creating layer ip

I1106 15:01:45.707713 13838 net.cpp:84] Creating Layer ip

I1106 15:01:45.707737 13838 net.cpp:406] ip <- data

I1106 15:01:45.707775 13838 net.cpp:380] ip -> ip

I1106 15:01:45.707849 13838 net.cpp:122] Setting up ip

I1106 15:01:45.707875 13838 net.cpp:129] Top shape: 200 2 (400)

I1106 15:01:45.707890 13838 net.cpp:137] Memory required for data: 8000

I1106 15:01:45.707963 13838 layer_factory.hpp:77] Creating layer loss

I1106 15:01:45.707993 13838 net.cpp:84] Creating Layer loss

I1106 15:01:45.708034 13838 net.cpp:406] loss <- ip

I1106 15:01:45.708055 13838 net.cpp:406] loss <- label

I1106 15:01:45.708083 13838 net.cpp:380] loss -> loss

I1106 15:01:45.708120 13838 layer_factory.hpp:77] Creating layer loss

I1106 15:01:45.708171 13838 net.cpp:122] Setting up loss

I1106 15:01:45.708195 13838 net.cpp:129] Top shape: (1)

I1106 15:01:45.708221 13838 net.cpp:132]     with loss weight 1

I1106 15:01:45.708261 13838 net.cpp:137] Memory required for data: 8008

I1106 15:01:45.708278 13838 net.cpp:198] loss needs backward computation.

I1106 15:01:45.708302 13838 net.cpp:198] ip needs backward computation.

I1106 15:01:45.708320 13838 net.cpp:200] data does not need backward computation.

I1106 15:01:45.708338 13838 net.cpp:242] This network produces output loss

I1106 15:01:45.708362 13838 net.cpp:255] Network initialization done.

I1106 15:01:45.708441 13838 solver.cpp:56] Solver scaffolding done.

Thread 1 "logreg_train" received signal SIGSEGV, Segmentation fault.

0x00007ffff7812426 in caffe::SGDSolver<double>::PreSolve() () from /home/nikfio/bin/caffe/build/lib/libcaffe.so.1.0.0

(gdb) bt

#0  0x00007ffff7812426 in caffe::SGDSolver<double>::PreSolve() () from /home/nikfio/bin/caffe/build/lib/libcaffe.so.1.0.0

#1  0x00000000004062a2 in caffe::SGDSolver<double>::SGDSolver(caffe::SolverParameter const&) ()

#2  0x00000000004057a6 in main ()

If you have ideas, please share them with me. Thank you.