Class faiss::gpu::StandardGpuResourcesImpl

class StandardGpuResourcesImpl : public faiss::gpu::GpuResources

Standard implementation of the GpuResources object that provides for a temporary memory manager

Public Functions

StandardGpuResourcesImpl()

~StandardGpuResourcesImpl() override

void noTempMemory()

Disable allocation of temporary memory; all temporary memory requests will call cudaMalloc / cudaFree at the point of use

void setTempMemory(size_t size)

Specify that we wish to use a certain fixed size of memory on all devices as temporary memory. This is the upper bound for the GPU memory that we will reserve. We will never go above 1.5 GiB on any GPU; smaller GPUs (with <= 4 GiB or <= 8 GiB) will use less memory than that. To avoid any temporary memory allocation, pass 0.

void setPinnedMemory(size_t size)

Set amount of pinned memory to allocate, for async GPU <-> CPU transfers

virtual void setDefaultStream(int device, cudaStream_t stream) override

Called to change the stream for work ordering. We do not own stream; i.e., it will not be destroyed when the GpuResources object gets cleaned up. We are guaranteed that all Faiss GPU work is ordered with respect to this stream upon exit from an index or other Faiss GPU call.

void revertDefaultStream(int device)

Revert the default stream to the original stream managed by this resources object, in case someone called setDefaultStream.

virtual cudaStream_t getDefaultStream(int device) override

Returns the stream for the given device on which all Faiss GPU work is ordered. We are guaranteed that all Faiss GPU work is ordered with respect to this stream upon exit from an index or other Faiss GPU call.

void setDefaultNullStreamAllDevices()

Called to change the work ordering streams to the null stream for all devices

void setLogMemoryAllocations(bool enable)

If enabled, will print every GPU memory allocation and deallocation to standard output

virtual void initializeForDevice(int device) override

Internal system calls.

Initialize resources for this device

virtual cublasHandle_t getBlasHandle(int device) override

Returns the cuBLAS handle that we use for the given device.

virtual std::vector<cudaStream_t> getAlternateStreams(int device) override

Returns the set of alternative streams that we use for the given device.

virtual void *allocMemory(const AllocRequest &req) override

Allocate non-temporary GPU memory.

virtual void deallocMemory(int device, void *in) override

Returns a previous allocation.

virtual size_t getTempMemoryAvailable(int device) const override

For MemorySpace::Temporary, how much space is immediately available without cudaMalloc allocation?

std::map<int, std::map<std::string, std::pair<int, size_t>>> getMemoryInfo() const

Export a description of memory used for Python.

virtual std::pair<void*, size_t> getPinnedMemory() override

Returns the available CPU pinned memory buffer.

virtual cudaStream_t getAsyncCopyStream(int device) override

Returns the stream on which we perform async CPU <-> GPU copies.

cublasHandle_t getBlasHandleCurrentDevice()

Calls getBlasHandle with the current device.

Functions provided by default

cudaStream_t getDefaultStreamCurrentDevice()

Calls getDefaultStream with the current device.

size_t getTempMemoryAvailableCurrentDevice() const

Calls getTempMemoryAvailable with the current device.

GpuMemoryReservation allocMemoryHandle(const AllocRequest &req)

Returns a temporary memory allocation via a RAII object.

void syncDefaultStream(int device)

Synchronizes the CPU with respect to the default stream for the given device

void syncDefaultStreamCurrentDevice()

Calls syncDefaultStream for the current device.

std::vector<cudaStream_t> getAlternateStreamsCurrentDevice()

Calls getAlternateStreams for the current device.

cudaStream_t getAsyncCopyStreamCurrentDevice()

Calls getAsyncCopyStream for the current device.

Private Functions

bool isInitialized(int device) const

Have GPU resources been initialized for this device yet?

Private Members

std::unordered_map<int, std::unordered_map<void*, AllocRequest>> allocs_

Set of currently outstanding memory allocations per device device -> (alloc request, allocated ptr)

std::unordered_map<int, std::unique_ptr<StackDeviceMemory>> tempMemory_

Temporary memory provider, per each device.

std::unordered_map<int, cudaStream_t> defaultStreams_

Our default stream that work is ordered on, one per each device.

std::unordered_map<int, cudaStream_t> userDefaultStreams_

This contains particular streams as set by the user for ordering, if any

std::unordered_map<int, std::vector<cudaStream_t>> alternateStreams_

Other streams we can use, per each device.

std::unordered_map<int, cudaStream_t> asyncCopyStreams_

Async copy stream to use for GPU <-> CPU pinned memory copies.

std::unordered_map<int, cublasHandle_t> blasHandles_

cuBLAS handle for each device

void *pinnedMemAlloc_

Pinned memory allocation for use with this GPU.

size_t pinnedMemAllocSize_

size_t tempMemSize_

Another option is to use a specified amount of memory on all devices

size_t pinnedMemSize_

Amount of pinned memory we should allocate.

bool allocLogging_

Whether or not we log every GPU memory allocation and deallocation.

Private Static Functions

static size_t getDefaultTempMemForGPU(int device, size_t requested)

Adjust the default temporary memory allocation based on the total GPU memory size