Device
#include <poplar/Device.hpp>
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namespace poplar
Poplar classes and functions.
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class Device
- #include <Device.hpp>
A device refers to a physical entity that can execute code.
Devices should be obtained from a poplar::DeviceManager object or from appropriate factory poplar::Device::createXXXDevice(). Devices can not be copied but can be moved.
Public Functions
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Device()
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virtual ~Device()
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unsigned getId() const
Get the numerical ID of this device as known by the DeviceManager.
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bool attach() const
Try and acquire this device and lock it to the current process.
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bool isAttached() const
Query if the device is attached.
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void detach() const
Release this device to other processes.
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void getDriverVersion(unsigned &major, unsigned &minor, unsigned &point) const
Retrieve driver version of the attached device.
Throws if the device is not attached or is not an IPU device.
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bool supportsRemoteBuffers() const
Retrieve availability of remote buffers from the attached device.
Throws if the device is not attached or is not an IPU device.
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bool hasGateway() const
Retrieve IPU-Gateway (such as in an IPU-M2000) availability from the attached device.
Throws an exception if the device is not attached or is not an IPU device.
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std::string getAttribute(IPUAttributes::AttributeId attributeId) const
Retrieve a device attribute string value keyed by attributeId.
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std::vector<int> getNumaNodesUsedForIPUs() const
Get the NUMA nodes that Poplar will use to execute code that communicates with each IPU that makes up this device.
If Poplar can’t execute code on the NUMA node for an IPU then this function returns -1 for that IPU. Poplar will interpret the -1 as disabling NUMA node pinning for that IPU.
Note that this function is not necessarily the same as getNumaTopology(), as it also handles NUMA node restrictions imposed by the Poplar process’ CPU affinity. For example on a machine with two NUMA nodes, with ids of 0 and 1, each connected to one CPU and one IPU then a Poplar process that is bound to CPU 1 will use CPU 1 to execute stream callbacks for IPUs on both NUMA node 0 and 1, so this function would return [-1, 1] whereas the getNumaTopology() would return [0, 1].
Note that if the look-up of available host NUMA nodes fails then this function will return a vector of
-1s, with one element for each IPU.
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std::vector<unsigned> getDriverIDs() const
Get the list of driver device IDs that make up this device.
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void reset() const
Reset the device’s state.
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Device createVirtualDevice(unsigned tilesPerIPU)
Create a virtual device with a restricted number of tiles per IPU.
This method provides a smaller “virtual” device whose target only shows a subset of the tiles on the underlying device.
The calling object becomes a null device (the underlying device is moved into the returned Device object).
Public Static Functions
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static Device createCPUDevice(unsigned numOfIPUs = 1)
Create a device that executes vertex code on the host CPU.
This is only suitable for running small amounts of code; for example, for functional testing. It may not reproduce exactly the same functionality as running on an IPU. Also, functions such as Engine::getTileClockFrequency() may not return meaningful results.
Note that the number of IPUs in a CPU device must equal the top-level replication factor of the graph that will run on the device (1 IPU per replica).
- Parameters
numOfIPUs – The number of IPUs the device will have.
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static Device createSimulatorDevice(const Target &target, const OptionFlags &options = {})
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Device()
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namespace core
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class Device