Hitrace
Overview
HiTraceMeter provides APIs for system performance tracing.
You can call the APIs provided by HiTraceMeter in your own service logic to effectively track service processes and check the system performance.
HiTraceChain provides APIs for cross-thread and cross-process distributed tracing. HiTraceChain generates a unique chain ID for a service process and passes it to various information (including application events, system events, and logs) specific to the service process. During debugging and fault locating, you can use the unique chain ID to quickly correlate various information related to the service process.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 10
Summary
Files
| Name | Description |
|---|---|
| trace.h | Defines APIs of the HiTraceMeter module for performance tracing. |
Structs
| Name | Description |
|---|---|
| struct HiTraceId | Defines a HiTraceId instance. |
Types
| Name | Description |
|---|---|
| typedef enum HiTraceId_ValidHiTraceId_Valid | Defines an enum for whether a HiTraceId instance is valid. |
| typedef enum HiTrace_VersionHiTrace_Version | Defines an enum for the HiTrace versions. |
| typedef enum HiTrace_FlagHiTrace_Flag | Defines an enum for the HiTrace flags. |
| typedef enum HiTrace_Tracepoint_TypeHiTrace_Tracepoint_Type | Defines an enum for the HiTrace tracepoint types. |
| typedef enum HiTrace_Communication_ModeHiTrace_Communication_Mode | Defines an enum for the HiTrace communication modes. |
| typedef struct HiTraceId HiTraceId | Defines a struct for the HiTraceId instance. |
Enums
| Name | Description |
|---|---|
| HiTraceId_Valid { HITRACE_ID_INVALID = 0, HITRACE_ID_VALID = 1 } | Enumerates whether a HiTraceId instance is valid. |
| HiTrace_Version { HITRACE_VER_1 = 0 } | Enumerates the HiTrace versions. |
| HiTrace_Flag { HITRACE_FLAG_DEFAULT = 0, HITRACE_FLAG_INCLUDE_ASYNC = 1 << 0, HITRACE_FLAG_DONOT_CREATE_SPAN = 1 << 1, HITRACE_FLAG_TP_INFO = 1 << 2, HITRACE_FLAG_NO_BE_INFO = 1 << 3, HITRACE_FLAG_DONOT_ENABLE_LOG = 1 << 4, HITRACE_FLAG_FAULT_TRIGGER = 1 << 5, HITRACE_FLAG_D2D_TP_INFO = 1 << 6 } |
Enumerates the HiTrace flags. |
| HiTrace_Tracepoint_Type { HITRACE_TP_CS = 0, HITRACE_TP_CR = 1, HITRACE_TP_SS = 2, HITRACE_TP_SR = 3, HITRACE_TP_GENERAL = 4 } |
Enumerates the HiTrace tracepoint types. |
| HiTrace_Communication_Mode { HITRACE_CM_DEFAULT = 0, HITRACE_CM_THREAD = 1, HITRACE_CM_PROCESS = 2, HITRACE_CM_DEVICE = 3 } | Enumerates the HiTrace communication modes. |
Functions
| Name | Description |
|---|---|
| HiTraceId OH_HiTrace_BeginChain (const char *name, int flags) | Starts tracing a process. |
| void OH_HiTrace_EndChain () | Stops tracing the process and clears the trace ID of the calling thread if the given trace ID is valid. Otherwise, no operation is performed. |
| HiTraceId OH_HiTrace_GetId () | Obtains the trace ID of the calling thread. If the calling thread does not have a trace ID, an invalid trace ID is returned. |
| void OH_HiTrace_SetId (const HiTraceId *id) | Sets the trace ID of the calling thread. If the ID is invalid, no operation is performed. |
| void OH_HiTrace_ClearId (void) | Clears the trace ID of the calling thread and invalidates it. |
| HiTraceId OH_HiTrace_CreateSpan (void) | Creates a span ID based on the trace ID of the calling thread. |
| void OH_HiTrace_Tracepoint (HiTrace_Communication_Mode mode, HiTrace_Tracepoint_Type type, const HiTraceId *id, const char *fmt,...) | Prints HiTrace information, including the trace ID. |
| void OH_HiTrace_InitId (HiTraceId *id) | Initializes a HiTraceId instance. |
| void OH_HiTrace_IdFromBytes (HiTraceId *id, const uint8_t *pIdArray, int len) | Creates a HiTraceId instance based on a byte array. |
| bool OH_HiTrace_IsIdValid (const HiTraceId *id) | Checks whether a HiTraceId instance is valid. |
| bool OH_HiTrace_IsFlagEnabled (const HiTraceId *id, HiTrace_Flag flag) | Checks whether the specified trace flag is enabled in a HiTraceId instance . |
| void OH_HiTrace_EnableFlag (const HiTraceId *id, HiTrace_Flag flag) | Enables the specified trace flag in a HiTraceId instance. |
| int OH_HiTrace_GetFlags (const HiTraceId *id) | Obtains the trace flags in a HiTraceId instance. |
| void OH_HiTrace_SetFlags (HiTraceId *id, int flags) | Sets trace flags in a HiTraceId instance. |
| uint64_t OH_HiTrace_GetChainId (const HiTraceId *id) | Obtains a trace chain ID. |
| void OH_HiTrace_SetChainId (HiTraceId *id, uint64_t chainId) | Sets the trace chain ID in a HiTraceId instance. |
| uint64_t OH_HiTrace_GetSpanId (const HiTraceId *id) | Obtains the span ID in a HiTraceId instance. |
| void OH_HiTrace_SetSpanId (HiTraceId *id, uint64_t spanId) | Sets the span ID in a HiTraceId instance. |
| uint64_t OH_HiTrace_GetParentSpanId (const HiTraceId *id) | Obtains the parent span ID in a HiTraceId instance. |
| void OH_HiTrace_SetParentSpanId (HiTraceId *id, uint64_t parentSpanId) | Sets the ParentSpanId in a HiTraceId instance. |
| int OH_HiTrace_IdToBytes (const HiTraceId *id, uint8_t *pIdArray, int len) | Converts a HiTraceId instance into a byte array for caching or transfer. |
| void OH_HiTrace_StartTrace (const char *name) | Marks the start of a synchronous trace. |
| void OH_HiTrace_FinishTrace (void) | Marks the end of a synchronous trace. |
| void OH_HiTrace_StartAsyncTrace (const char *name, int32_t taskId) | Marks the start of an asynchronous trace. |
| void OH_HiTrace_FinishAsyncTrace (const char *name, int32_t taskId) | Marks the end of an asynchronous trace. |
| void OH_HiTrace_CountTrace (const char *name, int64_t count) | Traces the value change of an integer variable based on its name. |
Variables
| Name | Description |
|---|---|
| uint64_t HiTraceId::valid: 1 | Whether a HiTraceId instance is valid. |
| uint64_t HiTraceId::ver: 3 | Version number of HiTraceId. |
| uint64_t HiTraceId::chainId: 60 | Chain ID of HiTraceId. |
| uint64_t HiTraceId::flags: 12 | Flag of HiTraceId. |
| uint64_t HiTraceId::spanId: 26 | Span ID of HiTraceId. |
| uint64_t HiTraceId::parentSpanId: 26 | Parent span ID of HiTraceId. |
Type Description
HiTrace_Communication_Mode
typedef enum HiTrace_Communication_Mode HiTrace_Communication_Mode
Description
Defines an enum for the HiTrace communication modes.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
HiTrace_Flag
typedef enum HiTrace_Flag HiTrace_Flag
Description
Defines an enum for the HiTrace flags.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
HiTrace_Tracepoint_Type
typedef enum HiTrace_Tracepoint_Type HiTrace_Tracepoint_Type
Description
Defines an enum for the HiTrace tracepoint types.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
HiTrace_Version
typedef enum HiTrace_Version HiTrace_Version
Description
Defines an enum for the HiTrace versions.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
HiTraceId_Valid
typedef enum HiTraceId_Valid HiTraceId_Valid
Description
Defines an enum for whether a HiTraceId instance is valid.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Enum Description
HiTrace_Communication_Mode
enum HiTrace_Communication_Mode
Description
Enumerates the HiTrace communication modes.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
| Value | Description |
|---|---|
| HITRACE_CM_DEFAULT | Unspecified SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_CM_THREAD | Inter-Thread Communication SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_CM_PROCESS | Inter-process communication (IPC) SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_CM_DEVICE | Inter-device communication SysCap: SystemCapability.HiviewDFX.HiTrace |
HiTrace_Flag
enum HiTrace_Flag
Description
Enumerates the HiTrace flags.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
| Value | Description |
|---|---|
| HITRACE_FLAG_DEFAULT | Default value SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_INCLUDE_ASYNC | Both synchronous and asynchronous calls are traced. By default, only synchronous calls are traced. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_DONOT_CREATE_SPAN | Do not create a child span. By default, a child span is created. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_TP_INFO | Trace points are automatically added to spans. By default, no trace point is added. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_NO_BE_INFO | Information about the start and end of the trace task is not printed. By default, information about the start and end of the trace task is printed. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_DONOT_ENABLE_LOG | The ID is not added to the log. By default, the ID is added to the log. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_FAULT_TRIGGER | Tracing is triggered by faults. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_FLAG_D2D_TP_INFO | Trace points are added only for call chain trace between devices. By default, device-to-device trace points are not added. SysCap: SystemCapability.HiviewDFX.HiTrace |
HiTrace_Tracepoint_Type
enum HiTrace_Tracepoint_Type
Description
Enumerates the HiTrace tracepoint types.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
| Value | Description |
|---|---|
| HITRACE_TP_CS | CS trace point SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_TP_CR | CR trace point SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_TP_SS | SS trace point SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_TP_SR | SR trace point SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_TP_GENERAL | General trace point SysCap: SystemCapability.HiviewDFX.HiTrace |
HiTrace_Version
enum HiTrace_Version
Description
Enumerates the HiTrace versions.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
| Value | Description |
|---|---|
| HITRACE_VER_1 | Version 1 SysCap: SystemCapability.HiviewDFX.HiTrace |
HiTraceId_Valid
enum HiTraceId_Valid
Description
Enumerates whether a HiTraceId instance is valid.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
| Value | Description |
|---|---|
| HITRACE_ID_INVALID | Invalid HiTraceId. SysCap: SystemCapability.HiviewDFX.HiTrace |
| HITRACE_ID_VALID | Valid HiTraceId. SysCap: SystemCapability.HiviewDFX.HiTrace |
Function Description
OH_HiTrace_BeginChain()
HiTraceId OH_HiTrace_BeginChain (const char * name, int flags )
Description
Starts tracing a process.
This API starts tracing, creates a HiTraceId instance, and sets it to the TLS of the calling thread. This API works only when it is called for the first time.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| name | Name of the traced service. |
| flags | Flags of the tracing. For details, see HiTrace_Flag. |
Returns
Generated HitraceId. For details, see HiTraceId.
OH_HiTrace_ClearId()
void OH_HiTrace_ClearId (void )
Description
Clears the trace ID of the calling thread and invalidates it.
This API clears the HiTraceId instance in the TLS of the calling thread.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
OH_HiTrace_CountTrace()
void OH_HiTrace_CountTrace (const char * name, int64_t count )
Description
Traces the value change of an integer variable based on its name.
This API can be executed for multiple times to trace the value change of a given integer variable at different time points.
Since: 10
Parameters
| Name | Description |
|---|---|
| name | Name of the integer variable. It does not need to be the same as the real variable name. |
| count | Integer value. Generally, an integer variable can be specified. |
OH_HiTrace_CreateSpan()
HiTraceId OH_HiTrace_CreateSpan (void )
Description
Creates a span ID based on the trace ID of the calling thread.
This API generates a new span and corresponding HiTraceId instance based on the HiTraceId instance in the TLS of the calling thread.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Returns
Valid span trace ID. For details, see HiTraceId. If span ID cannot be created, the ID of the calling thread is traced.
OH_HiTrace_EnableFlag()
void OH_HiTrace_EnableFlag (const HiTraceId * id, HiTrace_Flag flag )
Description
Enables the specified trace flag in a HiTraceId instance.
Sets trace flags in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | The trace ID for which the flag needs to be enabled. For details, see HiTraceId. |
| flag | The specified trace flag needs to be enabled in the trace ID. For details, see HiTrace_Flag. |
OH_HiTrace_EndChain()
void OH_HiTrace_EndChain ()
Description
Stops tracing the process and clears the trace ID of the calling thread if the given trace ID is valid. Otherwise, no operation is performed.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
OH_HiTrace_FinishAsyncTrace()
void OH_HiTrace_FinishAsyncTrace (const char * name, int32_t taskId )
Description
Marks the end of an asynchronous trace.
This API is called in the callback function after an asynchronous trace is complete. It is used with OH_HiTrace_StartAsyncTrace in pairs. Its name and task ID must be the same as those of OH_HiTrace_StartAsyncTrace.
Since: 10
Parameters
| Name | Description |
|---|---|
| name | Name of the asynchronous trace. |
| taskId | ID of the asynchronous trace. The start and end of an asynchronous trace task do not occur in sequence. Therefore, the start and end of an asynchronous trace need to be matched based on the task name and the unique task ID together. |
OH_HiTrace_FinishTrace()
void OH_HiTrace_FinishTrace (void )
Description
Marks the end of a synchronous trace.
This API must be used with OH_HiTrace_StartTrace in pairs. During trace data parsing, the system matches it with the OH_HiTrace_StartTrace API recently invoked in the service process.
Since: 10
OH_HiTrace_GetChainId()
uint64_t OH_HiTrace_GetChainId (const HiTraceId * id)
Description
Obtains a trace chain ID.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance for which you want to obtain the trace chain ID. For details, see HiTraceId. |
Returns
The trace chain ID of the specified HiTraceId instance.
OH_HiTrace_GetFlags()
int OH_HiTrace_GetFlags (const HiTraceId * id)
Description
Obtains the trace flags in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance for which you want to obtain the flag. For details, see HiTraceId. |
Returns
The trace flags set in the specified HiTraceId instance.
OH_HiTrace_GetId()
HiTraceId OH_HiTrace_GetId ()
Description Obtains the trace ID of the calling thread. If the calling thread does not have a trace ID, an invalid trace ID is returned.
Obtains the trace ID in TLS of the calling thread.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Returns
HiTraceId of the calling thread. If the calling thread does not have a trace ID, an invalid trace ID is returned.
OH_HiTrace_GetParentSpanId()
uint64_t OH_HiTrace_GetParentSpanId (const HiTraceId * id)
Description
Obtains the parent span ID in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance for which you want to obtain the parent span ID. For details, see HiTraceId. |
Returns
The parent span ID in the specified HiTraceId instance.
OH_HiTrace_GetSpanId()
uint64_t OH_HiTrace_GetSpanId (const HiTraceId * id)
Description
Obtains the span ID in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance for which you want to obtain the span ID. For details, see HiTraceId. |
Returns
The span ID in the specified HiTraceId instance.
OH_HiTrace_IdFromBytes()
void OH_HiTrace_IdFromBytes (HiTraceId * id, const uint8_t * pIdArray, int len )
Description
Creates a HiTraceId instance based on a byte array.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance to create. |
| pIdArray | Byte array. |
| len | Length of the byte array. |
OH_HiTrace_IdToBytes()
int OH_HiTrace_IdToBytes (const HiTraceId * id, uint8_t * pIdArray, int len )
Description
Converts a HiTraceId instance into a byte array for caching or transfer.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance to convert. For details, see HiTraceId. |
| pIdArray | Byte array. |
| len | Length of the byte array. |
Returns
The length of the byte array after conversion.
OH_HiTrace_InitId()
void OH_HiTrace_InitId (HiTraceId * id)
Description
Initializes a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance to initialize. |
OH_HiTrace_IsFlagEnabled()
bool OH_HiTrace_IsFlagEnabled (const HiTraceId * id, HiTrace_Flag flag )
Description
Checks whether the specified trace flag is enabled in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance to check. For details, see HiTraceId. |
| flag | Specified trace flag. For details, see HiTrace_Flag. |
Returns
Returns true if the specified trace flag is enabled; returns false otherwise.
OH_HiTrace_IsIdValid()
bool OH_HiTrace_IsIdValid (const HiTraceId * id)
Description
Checks whether a HiTraceId instance is valid.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance to check. For details, see HiTraceId. |
Returns
Returns true if the HiTraceId instance is valid; returns false otherwise.
OH_HiTrace_SetChainId()
void OH_HiTrace_SetChainId (HiTraceId * id, uint64_t chainId )
Description
Sets the trace chain ID in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance. For details, see HiTraceId. |
| chainId | Trace chain ID to set. |
OH_HiTrace_SetFlags()
void OH_HiTrace_SetFlags (HiTraceId * id, int flags )
Description
Sets trace flags in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance. For details, see HiTraceId. |
| flags | Trace flag to set. For details, see HiTrace_Flag. |
OH_HiTrace_SetId()
void OH_HiTrace_SetId (const HiTraceId * id)
Description
Sets the trace ID of the calling thread. If the ID is invalid, no operation is performed.
This API sets a HiTraceId instance to the TLS of the calling thread.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | Sets the trace ID of the calling thread. For details, see HiTraceId. |
OH_HiTrace_SetParentSpanId()
void OH_HiTrace_SetParentSpanId (HiTraceId * id, uint64_t parentSpanId )
Description
Sets the ParentSpanId in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance. For details, see HiTraceId. |
| parentSpanId | Parent span ID to set. |
OH_HiTrace_SetSpanId()
void OH_HiTrace_SetSpanId (HiTraceId * id, uint64_t spanId )
Description
Sets the span ID in a HiTraceId instance.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| id | HiTraceId instance for which you want to set the span ID. |
| spanId | Span ID to set. |
OH_HiTrace_StartAsyncTrace()
void OH_HiTrace_StartAsyncTrace (const char * name, int32_t taskId )
Description
Marks the start of an asynchronous trace.
This API is called to implement performance trace in asynchronous manner. The start and end of an asynchronous trace task do not occur in sequence. Therefore, a unique taskId is required to ensure proper data parsing. It is passed as an input parameter for the asynchronous API. This API is used with OH_HiTrace_FinishAsyncTrace in pairs. The two APIs that have the same name and task ID together form an asynchronous trace. If multiple trace tasks with the same name need to be performed at the same time or a trace task needs to be performed multiple times concurrently, different task IDs must be specified in OH_HiTrace_StartTrace. If the trace tasks with the same name are not performed at the same time, the same taskId can be used.
Since: 10
Parameters
| Name | Description |
|---|---|
| name | Name of the asynchronous trace. |
| taskId | ID of the asynchronous trace. The start and end of an asynchronous trace task do not occur in sequence. Therefore, the start and end of an asynchronous trace need to be matched based on the task name and the unique task ID together. |
OH_HiTrace_StartTrace()
void OH_HiTrace_StartTrace (const char * name)
Description
Marks the start of a synchronous trace.
This API is used with OH_HiTrace_FinishTrace in pairs. The two APIs can be used in nested mode. The stack data structure is used for matching during trace data parsing.
Since: 10
Parameters
| Name | Description |
|---|---|
| name | Name of the synchronous trace. |
OH_HiTrace_Tracepoint()
void OH_HiTrace_Tracepoint (HiTrace_Communication_Mode mode, HiTrace_Tracepoint_Type type, const HiTraceId * id, const char * fmt, ... )
Description
Prints HiTrace information, including the trace ID.
This API prints trace point information, including the communication mode, trace point type, timestamp, and span.
System capability: SystemCapability.HiviewDFX.HiTrace
Since: 12
Parameters
| Name | Description |
|---|---|
| mode | Communication mode for the trace point. For details, see HiTrace_Communication_Mode. |
| type | Trace point type. For details, see HiTrace_Tracepoint_Type. |
| id | Trace ID. For details, see HiTraceId. |
| fmt | Custom information to print. |
Variable Description
chainId
uint64_t HiTraceId::chainId
Description
Chain ID of HiTraceId.
flags
uint64_t HiTraceId::flags
Description
Flag of HiTraceId.
parentSpanId
uint64_t HiTraceId::parentSpanId
Description
Parent span ID of HiTraceId.
spanId
uint64_t HiTraceId::spanId
Description
Span ID of HiTraceId.
valid
uint64_t HiTraceId::valid
Description
Whether a HiTraceId instance is valid.
ver
uint64_t HiTraceId::ver
Description
Version number of HiTraceId.