new Profiler(onFrame)
Parameters:
| Name | Type | Description |
|---|---|---|
onFrame |
FrameCallback | a handle called for each recorded frame. The passed frame value may not be stored as it'll be updated with later frame information. Any information that is further stored by the handler should make copies or reduce the information. |
Members
(static, constant) START :number
A reference to the START record id constant.
Type:
- number
(static, constant) STOP :number
A reference to the STOP record id constant.
Type:
- number
_stack :Array.<ProfilerFrame>
A cache of ProfilerFrames to reuse when reporting the recorded frames in records.
Type:
- Array.<ProfilerFrame>
counters :Array.<ProfilerFrame>
An array of profiler frames separated by counter argument. Generally for Scratch these frames are separated by block function opcode. This tracks each time an opcode is called.
Type:
- Array.<ProfilerFrame>
increments :Array.<ProfilerFrame>
An array of frames incremented on demand instead as part of start and stop.
Type:
- Array.<ProfilerFrame>
nullFrame :ProfilerFrame
A frame with no id or argument.
Type:
onFrame :FrameCallback
A callback handle called with each decoded frame when reporting back all the recorded times.
Type:
records :Array.<*>
A series of START and STOP values followed by arguments. After recording is complete the full set of records is reported back by stepping through the series to connect the relative START and STOP information.
Type:
- Array.<*>
(constant) START :number
A reference to the START record id constant.
Type:
- number
(constant) STOP :number
A reference to the STOP record id constant.
Type:
- number
Methods
(static) available() → {boolean}
Profiler is only available on platforms with the Performance API.
Returns:
Can the Profiler run in this browser?
- Type
- boolean
(static) idByName(name) → {number}
Lookup or create an id for a frame name.
Parameters:
| Name | Type | Description |
|---|---|---|
name |
string | The name to return an id for. |
Returns:
The id for the passed name.
- Type
- number
(static) nameById(id) → {string}
Reverse lookup the name from a given frame id.
Parameters:
| Name | Type | Description |
|---|---|---|
id |
number | The id to search for. |
Returns:
The name for the given id.
- Type
- string
frame(id, arg) → {Object}
Find or create a ProfilerFrame-like object whose counter can be incremented outside of the Profiler.
Parameters:
| Name | Type | Description |
|---|---|---|
id |
number | The id returned by idByName for a name symbol. |
arg |
* | The argument for a frame that identifies it in addition to the id. |
Returns:
A ProfilerFrame-like whose count should be incremented for each call.
- Type
- Object
idByName(name) → {number}
Lookup or create an id for a frame name.
Parameters:
| Name | Type | Description |
|---|---|---|
name |
string | The name to return an id for. |
Returns:
The id for the passed name.
- Type
- number
increment(id)
Increment the number of times this symbol is called.
Parameters:
| Name | Type | Description |
|---|---|---|
id |
number | The id returned by idByName for a name symbol. |
nameById(id) → {string}
Reverse lookup the name from a given frame id.
Parameters:
| Name | Type | Description |
|---|---|---|
id |
number | The id to search for. |
Returns:
The name for the given id.
- Type
- string
reportFrames()
Decode records and report all frames to this.onFrame.
start(id, argnullable)
Start recording a frame of time for an id and optional argument.
Parameters:
| Name | Type | Attributes | Description |
|---|---|---|---|
id |
number | The id returned by idByName for a name symbol like Runtime._step. |
|
arg |
* |
<nullable> |
An arbitrary argument value to store with the frame. |
stop()
Stop the current frame.