C Specification

To request a timestamp and write the value to memory, call:

// Provided by VK_VERSION_1_0
void vkCmdWriteTimestamp(
    VkCommandBuffer                             commandBuffer,
    VkPipelineStageFlagBits                     pipelineStage,
    VkQueryPool                                 queryPool,
    uint32_t                                    query);

Parameters

  • commandBuffer is the command buffer into which the command will be recorded.

  • pipelineStage is a VkPipelineStageFlagBits value, specifying a stage of the pipeline.

  • queryPool is the query pool that will manage the timestamp.

  • query is the query within the query pool that will contain the timestamp.

Description

When vkCmdWriteTimestamp is submitted to a queue, it defines an execution dependency on commands that were submitted before it, and writes a timestamp to a query pool.

The first synchronization scope includes all commands that occur earlier in submission order. The synchronization scope is limited to operations on the pipeline stage specified by pipelineStage.

The second synchronization scope includes only the timestamp write operation.

Note

Implementations may write the timestamp at any stage that is logically later than stage.

Any timestamp write that happens-after another timestamp write in the same submission must not have a lower value unless its value overflows the maximum supported integer bit width of the query. If VK_KHR_calibrated_timestamps or VK_EXT_calibrated_timestamps is enabled, this extends to timestamp writes across all submissions on the same logical device: any timestamp write that happens-after another must not have a lower value unless its value overflows the maximum supported integer bit width of the query. Timestamps written by this command must be in the VK_TIME_DOMAIN_DEVICE_KHR time domain. If an overflow occurs, the timestamp value must wrap back to zero.

If vkCmdWriteTimestamp is called while executing a render pass instance that has multiview enabled, the timestamp uses N consecutive query indices in the query pool (starting at query) where N is the number of bits set in the view mask of the subpass or dynamic render pass the command is executed in. The resulting query values are determined by an implementation-dependent choice of one of the following behaviors:

  • The first query is a timestamp value and (if more than one bit is set in the view mask) zero is written to the remaining queries.

  • All N queries are timestamp values.

Either way, if two timestamps are written in the same subpass or dynamic render pass with multiview enabled, each of the N consecutive queries written for a timestamp must not have a lower value than the queries with corresponding indices written by the timestamp that happens-before unless the value overflows the maximum supported integer bit width of the query.

Valid Usage
Valid Usage (Implicit)
Host Synchronization

  • Host access to commandBuffer must be externally synchronized

  • Host access to the VkCommandPool that commandBuffer was allocated from must be externally synchronized

Command Properties
Command Buffer Levels Render Pass Scope Video Coding Scope Supported Queue Types Command Type

Primary
Secondary

Both

Both

VK_QUEUE_COMPUTE_BIT
VK_QUEUE_GRAPHICS_BIT
VK_QUEUE_OPTICAL_FLOW_BIT_NV
VK_QUEUE_TRANSFER_BIT
VK_QUEUE_VIDEO_DECODE_BIT_KHR
VK_QUEUE_VIDEO_ENCODE_BIT_KHR

Action
Conditional Rendering

vkCmdWriteTimestamp is not affected by conditional rendering

See Also

VK_VERSION_1_0, VkCommandBuffer, VkPipelineStageFlagBits, VkQueryPool

Document Notes

For more information, see the Vulkan Specification.

This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2026 The Khronos Group Inc.

SPDX-License-Identifier: CC-BY-4.0