PROTOCOLS
Sampler
Defined in fuchsia.memory.sampler/sampler.fidl
Interface used to exfiltrate process allocation information.
RecordAllocation
Record an allocation.
Request
| Name | Type |
|---|---|
payload |
SamplerRecordAllocationRequest
|
RecordDeallocation
Record a deallocation.
Request
| Name | Type |
|---|---|
payload |
SamplerRecordDeallocationRequest
|
SetProcessInfo
Communicate relevant process information to facilitate symbolization.
If called several times, the last process_name prevails, but the
module_map is added to the existing map for the process. If a client
needs to send a module_map that does not fit in a single message, they
can split it and send it across several messages.
Request
| Name | Type |
|---|---|
payload |
SamplerSetProcessInfoRequest
|
TABLES
ExecutableSegment
Defined in fuchsia.memory.sampler/sampler.fidl
Address region that corresponds to an executable segment in an ELF module.
| Ordinal | Field | Type | Description |
|---|---|---|---|
1 |
start_address |
uint64
|
Start of the region as mapped in memory. |
2 |
size |
uint64
|
Size of the range of addresses that are part of the region. |
3 |
relative_address |
uint64
|
Offset of the region in the ELF binary before loading. |
ModuleMap
Defined in fuchsia.memory.sampler/sampler.fidl
Information necessary for the symbolization of a module. Represents the subset of an ELF module relevant for the purposes of the profiler. The main use case for this map is the symbolization of stack traces.
| Ordinal | Field | Type | Description |
|---|---|---|---|
1 |
build_id |
vector<uint8>:20
|
Build ID, a string which uniquely identifies a module build. |
2 |
executable_segments |
vector<ExecutableSegment>
|
Collection of executable segments. |
SamplerRecordAllocationRequest
Defined in fuchsia.memory.sampler/sampler.fidl
| Ordinal | Field | Type | Description |
|---|---|---|---|
1 |
address |
uint64
|
Address of the allocation, to uniquely identify it. |
2 |
stack_trace |
StackTrace
|
Stack frames collected at the allocation point. A client is free to truncate their stack traces to a size below the maximum size of a message that can be sent over the channel. If a client sends a StackTrace that causes to exceed the maximum size of the message, then the record will be dropped until RFC-0196 is implemented. |
3 |
size |
uint64
|
Size (in bytes) of this allocation. |
SamplerRecordDeallocationRequest
Defined in fuchsia.memory.sampler/sampler.fidl
| Ordinal | Field | Type | Description |
|---|---|---|---|
1 |
address |
uint64
|
Address of the deallocation, to uniquely identify it. |
2 |
stack_trace |
StackTrace
|
Stack frames collected at the deallocation point. A client is free to truncate their stack traces to a size below the maximum size of a message that can be sent over the channel. If a client sends a StackTrace that causes to exceed the maximum size of the message, then the record will be dropped until RFC-0196 is implemented. |
SamplerSetProcessInfoRequest
Defined in fuchsia.memory.sampler/sampler.fidl
| Ordinal | Field | Type | Description |
|---|---|---|---|
1 |
process_name |
string:32
|
Name of the instrumented process. |
2 |
module_map |
vector<ModuleMap>
|
Current module layout, for symbolization. |
StackTrace
Defined in fuchsia.memory.sampler/sampler.fidl
A stack trace, as a collection of stack frames.
| Ordinal | Field | Type | Description |
|---|---|---|---|
1 |
stack_frames |
vector<uint64>
|
Ordered vector of frame pointers, from the narrower to the wider location. |
CONSTANTS
| Name | Value | Type | Description |
|---|---|---|---|
| BUILD_ID_BYTES |
20
|
uint32 |
A build ID is a 20 bytes long sequence. |