Function: device_can_access_peer
Applicability
Product |
Supported |
|---|---|
Atlas 350 Accelerator Card |
√ |
√ |
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√ |
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√ |
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√ |
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x |
Description
Queries whether memory copy is supported between devices.
Prototype
- C Prototype
1aclError aclrtDeviceCanAccessPeer(int32_t *canAccessPeer, int32_t deviceId, int32_t peerDeviceId)
- Python Function
1can_access_peer, ret = acl.rt.device_can_access_peer(dev_id, peer_dev_id)
Parameters
Parameter |
Description |
|---|---|
dev_id |
Int, specified device ID, which must be different from that of peer_dev_id. Must be in the range of [0, Device count – 1]. Call acl.rt.get_device_count to obtain the device count. |
peer_dev_id |
Int, specified device ID, which must be different from that of dev_id. Must be in the range of [0, Device count – 1]. Call acl.rt.get_device_count to obtain the device count. |
Return Value
Return Value |
Description |
|---|---|
can_access_peer |
Int, whether memory copy is supported between the device specified by dev_id and the device specified by peer_dev_id. 1: supported; 0: not supported. |
ret |
Int, error code. 0 on success; else, failure. |
Restrictions
- This API supports memory copy only in physical machines and containers.
- This API supports memory copy only between devices in the same PCIe switch. In AI Server applications, memory copy between devices is supported although they reside in different PCIe switches.
- This API supports memory copy only between devices in the same physical machine or container.
- This API supports memory copy only between devices of threads in the same process.
- This API supports memory copy between devices in the same PCIe switch only when the related ports of the host are enabled (such as the host BIOS).