[WIP] Platform helpers switches (#44)

* - platform helpers can be disabled on per-op basis now via Context::allowHelpers
- java has access to it as well

Signed-off-by: raver119 <raver119@gmail.com>

* global platform-helpers trigger

Signed-off-by: raver119 <raver119@gmail.com>

* few signatures renamed

Signed-off-by: raver119 <raver119@gmail.com>

* - few new env variables to follow
- maxThreads/masterThreads differentiation

Signed-off-by: raver119 <raver119@gmail.com>

* Javadoc update

Signed-off-by: raver119 <raver119@gmail.com>

libnd4j/blas/Environment.cpp

@@ -43,7 +43,7 @@
 namespace nd4j {
 
     nd4j::Environment::Environment() {
-        _tadThreshold.store(8);
+        _tadThreshold.store(1);
         _elementThreshold.store(1024);
         _verbose.store(false);
         _debug.store(false);
@@ -52,6 +52,7 @@ namespace nd4j {
         _leaks.store(false);
         _dataType.store(nd4j::DataType::FLOAT32);
         _maxThreads = std::thread::hardware_concurrency();
+        _maxMasterThreads = _maxThreads.load();
 
 #ifndef ANDROID
         const char* omp_threads = std::getenv("OMP_NUM_THREADS");
@@ -66,6 +67,94 @@ namespace nd4j {
                 // still do nothing
             }
         }
+
+        /**
+         * Defines size of thread pool used for parallelism
+         */
+        const char* max_threads = std::getenv("SD_MAX_THREADS");
+        if (max_threads != nullptr) {
+            try {
+                std::string t(max_threads);
+                int val = std::stoi(t);
+                _maxThreads.store(val);
+            } catch (std::invalid_argument &e) {
+                // just do nothing
+            } catch (std::out_of_range &e) {
+                // still do nothing
+            }
+        }
+
+        /**
+         * Defines max number of threads usable at once
+         */
+        const char* max_master_threads = std::getenv("SD_MASTER_THREADS");
+        if (max_master_threads != nullptr) {
+            try {
+                std::string t(max_master_threads);
+                int val = std::stoi(t);
+                _maxMasterThreads.store(val);
+            } catch (std::invalid_argument &e) {
+                // just do nothing
+            } catch (std::out_of_range &e) {
+                // still do nothing
+            }
+        }
+
+        /**
+         * If this env var is defined - we'll disallow use of platform-specific helpers (mkldnn, cudnn, etc)
+         */
+        const char* forbid_helpers = std::getenv("SD_FORBID_HELPERS");
+        if (max_master_threads != nullptr) {
+            _allowHelpers = false;
+        }
+
+        /**
+         * This var defines max amount of host memory library can allocate
+         */
+        const char* max_primary_memory = std::getenv("SD_MAX_PRIMARY_BYTES");
+        if (max_primary_memory != nullptr) {
+            try {
+                std::string t(max_primary_memory);
+                auto val = std::stol(t);
+                _maxTotalPrimaryMemory.store(val);
+            } catch (std::invalid_argument &e) {
+                // just do nothing
+            } catch (std::out_of_range &e) {
+                // still do nothing
+            }
+        }
+
+        /**
+         * This var defines max amount of special (i.e. device) memory library can allocate on all devices combined
+         */
+        const char* max_special_memory = std::getenv("SD_MAX_SPECIAL_BYTES");
+        if (max_special_memory != nullptr) {
+            try {
+                std::string t(max_special_memory);
+                auto val = std::stol(t);
+                _maxTotalSpecialMemory.store(val);
+            } catch (std::invalid_argument &e) {
+                // just do nothing
+            } catch (std::out_of_range &e) {
+                // still do nothing
+            }
+        }
+
+        /**
+         * This var defines max amount of special (i.e. device) memory library can allocate on all devices combined
+         */
+        const char* max_device_memory = std::getenv("SD_MAX_DEVICE_BYTES");
+        if (max_device_memory != nullptr) {
+            try {
+                std::string t(max_device_memory);
+                auto val = std::stol(t);
+                _maxDeviceMemory.store(val);
+            } catch (std::invalid_argument &e) {
+                // just do nothing
+            } catch (std::out_of_range &e) {
+                // still do nothing
+            }
+        }
 #endif
 
 #ifdef __CUDABLAS__
@@ -97,6 +186,18 @@ namespace nd4j {
         //
     }
 
+    void Environment::setMaxPrimaryMemory(uint64_t maxBytes) {
+        _maxTotalPrimaryMemory = maxBytes;
+    }
+
+    void Environment::setMaxSpecialyMemory(uint64_t maxBytes) {
+        _maxTotalSpecialMemory;
+    }
+
+    void Environment::setMaxDeviceMemory(uint64_t maxBytes) {
+        _maxDeviceMemory = maxBytes;
+    }
+
     Environment *Environment::getInstance() {
         if (_instance == 0)
             _instance = new Environment();
@@ -179,8 +280,16 @@ namespace nd4j {
         return _maxThreads.load();
     }
 
+    int Environment::maxMasterThreads() {
+        return _maxMasterThreads.load();
+    }
+
     void Environment::setMaxThreads(int max) {
-        _maxThreads.store(max);
+        //_maxThreads.store(max);
+    }
+
+    void Environment::setMaxMasterThreads(int max) {
+        //_maxMasterThreads = max;
     }
 
     bool Environment::precisionBoostAllowed() {
@@ -211,6 +320,14 @@ namespace nd4j {
         return _blasPatchVersion;
     }
 
+    bool Environment::helpersAllowed() {
+        return _allowHelpers.load();
+    }
+
+    void Environment::allowHelpers(bool reallyAllow) {
+        _allowHelpers.store(reallyAllow);
+    }
+
     nd4j::Environment *nd4j::Environment::_instance = 0;
 
 }

libnd4j/blas/Environment.h

@@ -37,10 +37,18 @@ namespace nd4j{
         std::atomic<bool> _debug;
         std::atomic<bool> _leaks;
         std::atomic<bool> _profile;
-        std::atomic<int> _maxThreads;
         std::atomic<nd4j::DataType> _dataType;
         std::atomic<bool> _precBoost;
         std::atomic<bool> _useMKLDNN{true};
+        std::atomic<bool> _allowHelpers{true};
+
+        std::atomic<int> _maxThreads;
+        std::atomic<int> _maxMasterThreads;
+
+        // these fields hold defaults
+        std::atomic<int64_t> _maxTotalPrimaryMemory{-1};
+        std::atomic<int64_t> _maxTotalSpecialMemory{-1};
+        std::atomic<int64_t> _maxDeviceMemory{-1};
 
 #ifdef __ND4J_EXPERIMENTAL__
         const bool _experimental = true;
@@ -74,6 +82,8 @@ namespace nd4j{
         void setDebug(bool reallyDebug);
         void setProfiling(bool reallyProfile);
         void setLeaksDetector(bool reallyDetect);
+        bool helpersAllowed();
+        void allowHelpers(bool reallyAllow);
         
         int tadThreshold();
         void setTadThreshold(int threshold);
@@ -84,6 +94,13 @@ namespace nd4j{
         int maxThreads();
         void setMaxThreads(int max);
 
+        int maxMasterThreads();
+        void setMaxMasterThreads(int max);
+
+        void setMaxPrimaryMemory(uint64_t maxBytes);
+        void setMaxSpecialyMemory(uint64_t maxBytes);
+        void setMaxDeviceMemory(uint64_t maxBytes);
+
         bool isUseMKLDNN() { return _useMKLDNN.load(); }
         void setUseMKLDNN(bool useMKLDNN) { _useMKLDNN.store(useMKLDNN); }
 

libnd4j/blas/NativeOps.h

@@ -1732,6 +1732,7 @@ typedef nd4j::graph::RandomGenerator OpaqueRandomGenerator;
 
 ND4J_EXPORT OpaqueContext* createGraphContext(int nodeId);
 ND4J_EXPORT OpaqueRandomGenerator* getGraphContextRandomGenerator(OpaqueContext* ptr);
+ND4J_EXPORT void ctxAllowHelpers(OpaqueContext* ptr, bool reallyAllow);
 ND4J_EXPORT void markGraphContextInplace(OpaqueContext* ptr, bool reallyInplace);
 ND4J_EXPORT void setGraphContextCudaContext(OpaqueContext* ptr, void *stream, void *reductionPointer, void *allocationPointer);
 ND4J_EXPORT void setGraphContextInputArray(OpaqueContext* ptr, int index, void *buffer, void *shapeInfo, void *specialBuffer, void *specialShapeInfo);

libnd4j/blas/cpu/NativeOps.cpp

@@ -2874,6 +2874,9 @@ void deleteGraphContext(nd4j::graph::Context* ptr) {
     delete ptr;
 }
 
+void ctxAllowHelpers(OpaqueContext* ptr, bool reallyAllow) {
+    ptr->allowHelpers(reallyAllow);
+}
 
 nd4j::graph::RandomGenerator* createRandomGenerator(Nd4jLong rootSeed, Nd4jLong nodeSeed) {
     return new nd4j::graph::RandomGenerator(rootSeed, nodeSeed);

libnd4j/blas/cuda/NativeOps.cu

@@ -3559,3 +3559,7 @@ bool isMinimalRequirementsMet() {
 bool isOptimalRequirementsMet() {
     return true;
 }
+
+void ctxAllowHelpers(OpaqueContext* ptr, bool reallyAllow) {
+    ptr->allowHelpers(reallyAllow);
+}

libnd4j/include/execution/Threads.h

@@ -107,11 +107,22 @@ namespace samediff {
          * @param increment
          * @return
          */
-        static int parallel_for(FUNC_1D function, int64_t start, int64_t stop, int64_t increment = 1, uint32_t numThreads = nd4j::Environment::getInstance()->maxThreads());
+        static int parallel_for(FUNC_1D function, int64_t start, int64_t stop, int64_t increment = 1, uint32_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads());
-
-        static int parallel_tad(FUNC_1D function, int64_t start, int64_t stop, int64_t increment = 1, uint32_t numThreads = nd4j::Environment::getInstance()->maxThreads());
 
         /**
+         * This function executes 1 dimensional loop for a given number of threads
+         *
+         * @param function
+         * @param start
+         * @param stop
+         * @param increment
+         * @param numThreads
+         * @return
+         */
+        static int parallel_tad(FUNC_1D function, int64_t start, int64_t stop, int64_t increment = 1, uint32_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads());
+
+        /**
+         * This method will execute function splitting 2 nested loops space with multiple threads
          *
          * @param function
          * @param numThreads
@@ -123,9 +134,10 @@ namespace samediff {
          * @param inc_y
          * @return
          */
-        static int parallel_for(FUNC_2D function, int64_t start_x, int64_t stop_x, int64_t inc_x, int64_t start_y, int64_t stop_y, int64_t inc_y, uint64_t numThreads = nd4j::Environment::getInstance()->maxThreads(), bool debug = false);
+        static int parallel_for(FUNC_2D function, int64_t start_x, int64_t stop_x, int64_t inc_x, int64_t start_y, int64_t stop_y, int64_t inc_y, uint64_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads(), bool debug = false);
 
         /**
+         * This method will execute function splitting 3 nested loops space with multiple threads
          *
          * @param function
          * @param numThreads
@@ -140,7 +152,7 @@ namespace samediff {
          * @param inc_z
          * @return
          */
-        static int parallel_for(FUNC_3D function, int64_t start_x, int64_t stop_x, int64_t inc_x, int64_t start_y, int64_t stop_y, int64_t inc_y, int64_t start_z, int64_t stop_z, int64_t inc_z, uint64_t numThreads = nd4j::Environment::getInstance()->maxThreads());
+        static int parallel_for(FUNC_3D function, int64_t start_x, int64_t stop_x, int64_t inc_x, int64_t start_y, int64_t stop_y, int64_t inc_y, int64_t start_z, int64_t stop_z, int64_t inc_z, uint64_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads());
 
         /**
          *
@@ -148,11 +160,11 @@ namespace samediff {
          * @param numThreads
          * @return
          */
-        static int parallel_do(FUNC_DO function, uint64_t numThreads = nd4j::Environment::getInstance()->maxThreads());
+        static int parallel_do(FUNC_DO function, uint64_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads());
 
-        static int64_t parallel_long(FUNC_RL function, FUNC_AL aggregator, int64_t start, int64_t stop, int64_t increment = 1, uint64_t numThreads = nd4j::Environment::getInstance()->maxThreads());
+        static int64_t parallel_long(FUNC_RL function, FUNC_AL aggregator, int64_t start, int64_t stop, int64_t increment = 1, uint64_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads());
 
-        static double parallel_double(FUNC_RD function, FUNC_AD aggregator, int64_t start, int64_t stop, int64_t increment = 1, uint64_t numThreads = nd4j::Environment::getInstance()->maxThreads());
+        static double parallel_double(FUNC_RD function, FUNC_AD aggregator, int64_t start, int64_t stop, int64_t increment = 1, uint64_t numThreads = nd4j::Environment::getInstance()->maxMasterThreads());
     };
 }
 

libnd4j/include/graph/Context.h

@@ -58,9 +58,12 @@ namespace nd4j {
 
             std::vector<nd4j::DataType> _dataTypes;
 
+            // fields for fast execution (out-of-graph ops use)
             std::vector<NDArray*> _fastpath_in;
             std::vector<NDArray*> _fastpath_out;
             std::vector<NDArray*> _handles;
+
+            bool _helpersAllowed = true;
         public:
             Context(ContextPrototype* prototype, VariableSpace* variableSpace);
 
@@ -188,6 +191,10 @@ namespace nd4j {
             void setBArguments(bool *arguments, int numberOfArguments);
 
             void setCudaContext(Nd4jPointer cudaStream, Nd4jPointer reductionPointer, Nd4jPointer allocationPointer);
+
+
+            void allowHelpers(bool reallyAllow);
+            bool helpersAllowed();
         };
     }
 }

libnd4j/include/graph/impl/Context.cpp

@@ -461,6 +461,14 @@ namespace nd4j {
                 v->setContext(_context);
 #endif
         }
+
+        void Context::allowHelpers(bool reallyAllow) {
+            _helpersAllowed = reallyAllow;
+        }
+
+        bool Context::helpersAllowed() {
+            return _helpersAllowed;
+        }
     }
 }
 

libnd4j/include/ops/declarable/impl/DeclarableOp.cpp

@@ -506,12 +506,15 @@ namespace nd4j {
             Nd4jStatus status;
             bool hasHelper = false;
 
-            // if we have platform-specific helper for this op - invoke it
+            // platform helpers use might be forbidden for various reasons, so we'll check it out first
-            if (OpRegistrator::getInstance()->hasHelper(this->getOpHash())) {
+            if (block->helpersAllowed() && nd4j::Environment::getInstance()->helpersAllowed()) {
-                auto helper =  OpRegistrator::getInstance()->getPlatformHelper(this->getOpHash());
+                // if we have platform-specific helper for this op - invoke it
-                if (helper->isUsable(*block)) {
+                if (OpRegistrator::getInstance()->hasHelper(this->getOpHash())) {
-                    status = helper->invokeHelper(*block);
+                    auto helper = OpRegistrator::getInstance()->getPlatformHelper(this->getOpHash());
-                    hasHelper = true;
+                    if (helper->isUsable(*block)) {
+                        status = helper->invokeHelper(*block);
+                        hasHelper = true;
+                    }
                 }
             }
 

nd4j/nd4j-backends/nd4j-api-parent/nd4j-api/src/main/java/org/nd4j/linalg/api/ops/OpContext.java

@@ -128,4 +128,12 @@ public interface OpContext extends AutoCloseable {
      * @param reallyInplace
      */
     void markInplace(boolean reallyInplace);
+
+    /**
+     * This method allows to enable/disable use of platform helpers within ops. I.e. mkldnn or cuDNN.
+     * PLEASE NOTE: default value is True
+     *
+     * @param reallyAllow
+     */
+    void allowHelpers(boolean reallyAllow);
 }

nd4j/nd4j-backends/nd4j-api-parent/nd4j-native-api/src/main/java/org/nd4j/nativeblas/NativeOps.java

@@ -1123,6 +1123,7 @@ public interface NativeOps {
     void setGraphContextTArguments(OpaqueContext ptr, DoublePointer arguments, int numberOfArguments);
     void setGraphContextIArguments(OpaqueContext ptr, LongPointer arguments, int numberOfArguments);
     void setGraphContextBArguments(OpaqueContext ptr, BooleanPointer arguments, int numberOfArguments);
+    void ctxAllowHelpers(OpaqueContext ptr, boolean reallyAllow);
     void deleteGraphContext(OpaqueContext ptr);
 
     OpaqueRandomGenerator createRandomGenerator(long rootSeed, long nodeSeed);

nd4j/nd4j-backends/nd4j-backend-impls/nd4j-cuda/src/main/java/org/nd4j/linalg/jcublas/ops/executioner/CudaOpContext.java

@@ -136,4 +136,9 @@ public class CudaOpContext extends BaseOpContext implements OpContext {
     public void markInplace(boolean reallyInplace) {
         nativeOps.markGraphContextInplace(context, reallyInplace);
     }
+
+    @Override
+    public void allowHelpers(boolean reallyAllow) {
+        nativeOps.ctxAllowHelpers(context, reallyAllow);
+    }
 }

nd4j/nd4j-backends/nd4j-backend-impls/nd4j-cuda/src/main/java/org/nd4j/nativeblas/Nd4jCuda.java

@@ -1,4 +1,4 @@
-// Targeted by JavaCPP version 1.5.1-1: DO NOT EDIT THIS FILE
+// Targeted by JavaCPP version 1.5.2: DO NOT EDIT THIS FILE
 
 package org.nd4j.nativeblas;
 
@@ -575,6 +575,8 @@ public class Nd4jCuda extends org.nd4j.nativeblas.Nd4jCudaHelper {
         public native void setDebug(@Cast("bool") boolean reallyDebug);
         public native void setProfiling(@Cast("bool") boolean reallyProfile);
         public native void setLeaksDetector(@Cast("bool") boolean reallyDetect);
+        public native @Cast("bool") boolean helpersAllowed();
+        public native void allowHelpers(@Cast("bool") boolean reallyAllow);
         
         public native int tadThreshold();
         public native void setTadThreshold(int threshold);
@@ -585,6 +587,13 @@ public class Nd4jCuda extends org.nd4j.nativeblas.Nd4jCudaHelper {
         public native int maxThreads();
         public native void setMaxThreads(int max);
 
+        public native int maxMasterThreads();
+        public native void setMaxMasterThreads(int max);
+
+        public native void setMaxPrimaryMemory(@Cast("uint64_t") long maxBytes);
+        public native void setMaxSpecialyMemory(@Cast("uint64_t") long maxBytes);
+        public native void setMaxDeviceMemory(@Cast("uint64_t") long maxBytes);
+
         public native @Cast("bool") boolean isUseMKLDNN();
         public native void setUseMKLDNN(@Cast("bool") boolean useMKLDNN);
 
@@ -3087,6 +3096,7 @@ public native void deleteShapeBuffer(OpaqueConstantDataBuffer ptr);
 
 public native OpaqueContext createGraphContext(int nodeId);
 public native OpaqueRandomGenerator getGraphContextRandomGenerator(OpaqueContext ptr);
+public native void ctxAllowHelpers(OpaqueContext ptr, @Cast("bool") boolean reallyAllow);
 public native void markGraphContextInplace(OpaqueContext ptr, @Cast("bool") boolean reallyInplace);
 public native void setGraphContextCudaContext(OpaqueContext ptr, Pointer stream, Pointer reductionPointer, Pointer allocationPointer);
 public native void setGraphContextInputArray(OpaqueContext ptr, int index, Pointer buffer, Pointer shapeInfo, Pointer specialBuffer, Pointer specialShapeInfo);
@@ -5458,6 +5468,10 @@ NDArray& NDArray::operator()(const Nd4jLong* idx) {
 
         
 
+        
+
+        
+
 
         
 
@@ -6741,6 +6755,10 @@ NDArray& NDArray::operator()(const Nd4jLong* idx) {
             public native void setBArguments(@Cast("bool*") boolean[] arguments, int numberOfArguments);
 
             public native void setCudaContext(@Cast("Nd4jPointer") Pointer cudaStream, @Cast("Nd4jPointer") Pointer reductionPointer, @Cast("Nd4jPointer") Pointer allocationPointer);
+
+
+            public native void allowHelpers(@Cast("bool") boolean reallyAllow);
+            public native @Cast("bool") boolean helpersAllowed();
         }
     
 

nd4j/nd4j-backends/nd4j-backend-impls/nd4j-native/src/main/java/org/nd4j/linalg/cpu/nativecpu/ops/CpuOpContext.java

@@ -105,4 +105,9 @@ public class CpuOpContext extends BaseOpContext implements OpContext {
     public void markInplace(boolean reallyInplace) {
         nativeOps.markGraphContextInplace(context, reallyInplace);
     }
+
+    @Override
+    public void allowHelpers(boolean reallyAllow) {
+        nativeOps.ctxAllowHelpers(context, reallyAllow);
+    }
 }

nd4j/nd4j-backends/nd4j-backend-impls/nd4j-native/src/main/java/org/nd4j/nativeblas/Nd4jCpu.java

@@ -575,6 +575,8 @@ public class Nd4jCpu extends org.nd4j.nativeblas.Nd4jCpuHelper {
         public native void setDebug(@Cast("bool") boolean reallyDebug);
         public native void setProfiling(@Cast("bool") boolean reallyProfile);
         public native void setLeaksDetector(@Cast("bool") boolean reallyDetect);
+        public native @Cast("bool") boolean helpersAllowed();
+        public native void allowHelpers(@Cast("bool") boolean reallyAllow);
         
         public native int tadThreshold();
         public native void setTadThreshold(int threshold);
@@ -585,6 +587,13 @@ public class Nd4jCpu extends org.nd4j.nativeblas.Nd4jCpuHelper {
         public native int maxThreads();
         public native void setMaxThreads(int max);
 
+        public native int maxMasterThreads();
+        public native void setMaxMasterThreads(int max);
+
+        public native void setMaxPrimaryMemory(@Cast("uint64_t") long maxBytes);
+        public native void setMaxSpecialyMemory(@Cast("uint64_t") long maxBytes);
+        public native void setMaxDeviceMemory(@Cast("uint64_t") long maxBytes);
+
         public native @Cast("bool") boolean isUseMKLDNN();
         public native void setUseMKLDNN(@Cast("bool") boolean useMKLDNN);
 
@@ -3087,6 +3096,7 @@ public native void deleteShapeBuffer(OpaqueConstantDataBuffer ptr);
 
 public native OpaqueContext createGraphContext(int nodeId);
 public native OpaqueRandomGenerator getGraphContextRandomGenerator(OpaqueContext ptr);
+public native void ctxAllowHelpers(OpaqueContext ptr, @Cast("bool") boolean reallyAllow);
 public native void markGraphContextInplace(OpaqueContext ptr, @Cast("bool") boolean reallyInplace);
 public native void setGraphContextCudaContext(OpaqueContext ptr, Pointer stream, Pointer reductionPointer, Pointer allocationPointer);
 public native void setGraphContextInputArray(OpaqueContext ptr, int index, Pointer buffer, Pointer shapeInfo, Pointer specialBuffer, Pointer specialShapeInfo);
@@ -6745,6 +6755,10 @@ NDArray& NDArray::operator()(const Nd4jLong* idx) {
             public native void setBArguments(@Cast("bool*") boolean[] arguments, int numberOfArguments);
 
             public native void setCudaContext(@Cast("Nd4jPointer") Pointer cudaStream, @Cast("Nd4jPointer") Pointer reductionPointer, @Cast("Nd4jPointer") Pointer allocationPointer);
+
+
+            public native void allowHelpers(@Cast("bool") boolean reallyAllow);
+            public native @Cast("bool") boolean helpersAllowed();
         }
     
 
@@ -11383,6 +11397,7 @@ public static final int TAD_THRESHOLD = TAD_THRESHOLD();
 // #elif _MSC_VER
 // #define FORCEINLINE __forceinline
 // #elif __GNUC__
+// #define INLINE_LOOPS
 // #define FORCEINLINE __attribute__((always_inline)) inline 
 // #elif __CUDACC__ 
 // #else

nd4j/nd4j-common/src/main/java/org/nd4j/config/ND4JEnvironmentVars.java

@@ -137,6 +137,39 @@ public class ND4JEnvironmentVars {
      */
     public static final String ND4J_IGNORE_AVX = "ND4J_IGNORE_AVX";
 
+    /**
+     * This variable defines how many threads will be used in ThreadPool for parallel execution of linear algebra.
+     * Default value: number of threads supported by this system.
+     */
+    public static final String SD_MAX_THREADS = "SD_MAX_THREADS";
+
+    /**
+     * This variable defines how many threads will be used for any 1 linear algebra operation.
+     * Default value: number of threads supported by this system.
+     */
+    public static final String SD_MASTER_THREADS = "SD_MASTER_THREADS";
+
+    /**
+     * If set, this variable disables use of optimized platform helpers (i.e. mkldnn or cuDNN)
+     */
+    public static final String SD_FORBID_HELPERS = "SD_FORBID_HELPERS";
+
+    /**
+     * If set, this variables defines how much memory application is allowed to use off-heap.
+     * PLEASE NOTE: this option is separate from JVM XMS/XMX options
+     */
+    public static final String SD_MAX_PRIMARY_BYTES = "SD_MAX_PRIMARY_BYTES";
+
+    /**
+     * If set, this variable defines how much memory application is allowed to use ON ALL computational devices COMBINED.
+     */
+    public static final String SD_MAX_SPECIAL_BYTES = "SD_MAX_SPECIAL_BYTES";
+
+    /**
+     * If set, this variable defines how much memory application is allowed to use on any one computational device
+     */
+    public static final String SD_MAX_DEVICE_BYTES = "SD_MAX_DEVICE_BYTES";
+
     private ND4JEnvironmentVars() {
     }
 }