Method and apparatus for trace data collection
A method is provided for collecting trace data items generated by a plurality of trace points, the method comprising: allocating a ring buffer in a first memory, the ring buffer including a plurality of trace buffers; when any of the trace points is executed, storing a trace data item generated by the trace point in one of the plurality of trace buffers that is identified by a given value of a ring pointer; retrieving the trace data item from the trace buffer based on at least one of: (i) a first timestamp that is generated when the trace data item is stored in the trace buffer, and (ii) a second timestamp indicating a time when the ring pointer was assigned the given value; and storing the retrieved trace data item in a second memory device.
1. A method for collecting trace data items generated by a plurality of trace points, the method comprising:
allocating a ring buffer in a first memory device, the ring buffer including a plurality of trace buffers;
incrementing a ring pointer to assign a given value to the ring pointer;
when any of the trace points is executed, storing a trace data item generated by the trace point in one of the plurality of trace buffers that is identified by the given value of the ring pointer;
retrieving the trace data item from the trace buffer based on a timestamp indicating a time when the ring pointer was assigned the given value, wherein retrieving the trace data item based on the timestamp includes: performing a search of a ring pointer database based on the given value to identify a timestamp corresponding to a most recent time when the ring pointer was assigned the given value, retrieving the timestamp as a result of the search, detecting a distance between a current time and a time indicated by the timestamp, detecting whether the distance exceeds a threshold, and retrieving the trace data item only when the distance exceeds the threshold; and
storing the retrieved trace data item in a second memory device.
2. The method of claim 1 , wherein the plurality of trace points is contained in one or more files, the method further comprising:
pre-processing the one or more files before any of the trace points is executed to identify a size of a largest trace data item that is generated by any of the trace points,
wherein the ring buffer is allocated based on the size of the largest trace data item that is generated by any of the trace points, such that each trace buffer in the ring buffer has a respective size that is greater than or equal to the size of the largest trace data item that is generated by any of the trace points.
3. The method of claim 1 , wherein the plurality of trace points is contained in one or more files, the method further comprising:
pre-processing the one or more files before any of the trace points is executed to identify a respective format of each of the trace data items, and, for each trace point, inserting one or more processor-executable instructions into a file containing the trace point, which when executed cause a format ID to be included into the trace data item, or other data, that is generated by the trace point, the format ID identifying the format of the trace data item that is generated by the trace point.
4. A method for collecting trace data items generated by a plurality of trace points, the method comprising:
allocating a ring buffer in a first memory device, the ring buffer including a plurality of trace buffers;
when any of the trace points is executed, storing a trace data item generated by the trace point in one of the plurality of trace buffers that is identified by a given value of a ring pointer;
retrieving the trace data item from the trace buffer based on at least one of: (i) a first timestamp that is generated when the trace data item is stored in the trace buffer, and (ii) a second timestamp indicating a time when the ring pointer was assigned the given value;
detecting a first value of the ring pointer that is current when the retrieving of the trace data item is initiated;
detecting a second value of the ring pointer that is current when the retrieving of the trace data item is completed;
detecting whether the ring pointer has been re-assigned the given value before the retrieving of the trace data item is completed, the detecting being based on the first value of the ring pointer and the second value of the ring pointer; and
storing the retrieved trace data item in a second memory device, wherein the retrieved trace data item is stored in the second memory device only when the ring pointer has not been re-assigned the given value before the retrieving of the trace data item is completed.
5. An apparatus for collecting trace data items generated by a plurality of trace points, the apparatus comprising:
a first memory device;
a second memory device; and
at least one processor operatively coupled to the first memory device and the second memory device, the at least one processor being configured to:
allocate a ring buffer on the first memory device, the ring buffer including a plurality of trace buffers;
assign a given value to a ring pointer by incrementing the ring pointer,
when any of the trace points is executed, store a trace data item generated by the trace point in one of the plurality of trace buffers that is identified by the given value of the ring pointer;
retrieve the trace data item from the trace buffer based on a timestamp indicating a time when the ring pointer was assigned the given value, wherein the retrieval of the trace data item based on the timestamp includes: performing a search of a ring pointer database based on the given value to identify a timestamp corresponding to a most recent time when the ring pointer was assigned the given value, retrieving the timestamp as a result of the search, detecting a distance between a current time and a time indicated by the timestamp, detecting whether the distance exceeds a threshold, and retrieve the trace data item only when the distance exceeds the threshold; and
store the retrieved trace data item on the second memory device.
6. The apparatus of claim 5 , wherein the plurality of trace points is contained in one or more files, and the at least one processor is further configured to:
pre-process the one or more files before any of the trace points is executed to identify a size of a largest trace data item that is generated by any of the trace points,
wherein the ring buffer is allocated based on the size of the largest trace data item that is generated by any of the trace points, such that each trace buffer in the ring buffer has a respective size that is greater than or equal to the size of the largest trace data item that is generated by any of the trace points.
7. The apparatus of claim 5 , wherein the plurality of trace points is contained in one or more files, and the at least one processor is further configured to:
pre-process the one or more files before any of the trace points is executed to identify a respective format of each of the trace data items, and for each trace point, insert one or more processor-executable instructions into a file containing the trace point, which when executed cause a format ID to be included into the trace data item, or other data, that is generated by the trace point, the format ID identifying the format of the trace data item that is generated by the trace point.
8. An apparatus for collecting trace data items generated by a plurality of trace points, the apparatus comprising:
a first memory device;
a second memory device; and
at least one processor operatively coupled to the first memory device and the second memory device, the at least one processor being configured to:
allocate a ring buffer on the first memory device, the ring buffer including a plurality of trace buffers;
when any of the trace points is executed, store a trace data item generated by the trace point in one of the plurality of trace buffers that is identified by a given value of a ring pointer;
retrieve the trace data item from the trace buffer based on at least one of: (i) a first timestamp that is generated when the trace data item is stored in the trace buffer, and (ii) a second timestamp indicating a time when the ring pointer was assigned the given value;
detect a first value of the ring pointer that is current when the retrieval of the trace data item is initiated;
detect a second value of the ring pointer that is current when the retrieval of the trace data item is completed;
detect whether the ring pointer has been re-assigned the given value before the retrieval of the trace data item is completed, the detection being based on the first value of the ring pointer and the second value of the ring pointer; and
store the retrieved trace data item on the second memory device, the retrieved trace data item being stored in permanent storage only when the ring pointer has not been re-assigned the given value before the retrieval of the trace data item is completed.