| 1 | = babeltrace2-sink.ctf.fs(7) |
| 2 | :manpagetype: component class |
| 3 | :revdate: 14 September 2019 |
| 4 | |
| 5 | |
| 6 | == NAME |
| 7 | |
| 8 | babeltrace2-sink.ctf.fs - Babeltrace 2's file system CTF sink component |
| 9 | class |
| 10 | |
| 11 | |
| 12 | == DESCRIPTION |
| 13 | |
| 14 | A Babeltrace~2 compcls:sink.ctf.fs component writes the messages it |
| 15 | consumes to one or more https://diamon.org/ctf/[CTF]~1.8 traces on |
| 16 | the file system. |
| 17 | |
| 18 | ---- |
| 19 | +-------------+ |
| 20 | | sink.ctf.fs | |
| 21 | | +--> CTF trace(s) on |
| 22 | Messages -->@ in | the file system |
| 23 | +-------------+ |
| 24 | ---- |
| 25 | |
| 26 | include::common-see-babeltrace2-intro.txt[] |
| 27 | |
| 28 | A compcls:sink.ctf.fs component does not merge traces: it writes the |
| 29 | messages of different input traces to different output traces. |
| 30 | |
| 31 | |
| 32 | === Special trace IR to CTF translations |
| 33 | |
| 34 | A compcls:sink.ctf.fs component makes a best effort to write CTF traces |
| 35 | that are semantically equivalent to the input traces. As of this |
| 36 | version, the component writes CTF~1.8 traces, so the following |
| 37 | field class translations can occur: |
| 38 | |
| 39 | * The component translates a boolean field class to a CTF unsigned 8-bit |
| 40 | integer field class. |
| 41 | + |
| 42 | The unsigned integer field's value is 0 when the boolean field's value |
| 43 | is false and 1 when the boolean field's value is true. |
| 44 | |
| 45 | * The component translates a bit array field to a CTF unsigned |
| 46 | integer field class having the same length. |
| 47 | |
| 48 | * The component translates an option field class to a CTF variant |
| 49 | field class where the options are an empty structure field class |
| 50 | and the optional field class itself. |
| 51 | + |
| 52 | The empty structure field is selected when the option field has no |
| 53 | field. |
| 54 | |
| 55 | In all the cases above, the component adds a comment in the metadata |
| 56 | stream, above the field class, to indicate that a special translation |
| 57 | occurred. |
| 58 | |
| 59 | |
| 60 | === Input message constraints |
| 61 | |
| 62 | Because of limitations in CTF~1.8 regarding how discarded events |
| 63 | and packets are encoded: |
| 64 | |
| 65 | * If a stream class supports discarded events and the |
| 66 | param:ignore-discarded-events parameter is :not: true: |
| 67 | |
| 68 | ** The stream class must support packets. |
| 69 | ** Discarded events messages must have times. |
| 70 | ** Any discarded events message must occur between a packet end |
| 71 | and a packet beginning message. |
| 72 | ** The beginning time of a discarded events message must be the same |
| 73 | as the time of the last packet end message. |
| 74 | ** The end time of a discarded events message must be the same |
| 75 | as the time of the next packet end message. |
| 76 | ** Time ranges of discarded events messages must not overlap. |
| 77 | |
| 78 | * If a stream class supports discarded packets and the |
| 79 | param:ignore-discarded-packets parameter is :not: true: |
| 80 | |
| 81 | ** The stream class must support packets. |
| 82 | ** Discarded packets messages must have times. |
| 83 | ** The beginning time of a discarded events message must be the same |
| 84 | as the time of the last packet end message. |
| 85 | ** The end time of a discarded events message must be the same |
| 86 | as the time of the next packet beginning message. |
| 87 | ** Time ranges of discarded packets messages must not overlap. |
| 88 | |
| 89 | The messages which a compcls:source.ctf.fs component creates satisfy all |
| 90 | the requirements above. |
| 91 | |
| 92 | If a discarded events or packets message has no events/packets count, |
| 93 | the compcls:sink.ctf.fs component adds 1 to the corresponding CTF |
| 94 | stream's counter. |
| 95 | |
| 96 | |
| 97 | === Alignment and byte order |
| 98 | |
| 99 | A compcls:sink.ctf.fs component always aligns data fields as such: |
| 100 | |
| 101 | Integer fields with a size which is not a multiple of 8:: |
| 102 | 1-bit. |
| 103 | |
| 104 | All other scalar fields (integer, enumeration, real, string):: |
| 105 | 8-bit. |
| 106 | |
| 107 | The component writes fields using the machine's native byte order. As of |
| 108 | this version, there's no way to force a custom byte order. |
| 109 | |
| 110 | |
| 111 | [[output-path]] |
| 112 | === Output path |
| 113 | |
| 114 | The path of a CTF trace is the directory which directly contains the |
| 115 | metadata and data stream files. |
| 116 | |
| 117 | The current strategy to build a path in which to write the streams of |
| 118 | a given input trace is, in this order: |
| 119 | |
| 120 | . If the param:assume-single-trace parameter is true, then the output |
| 121 | trace path to use for the single input trace is the directory |
| 122 | specified by the param:path parameter. |
| 123 | |
| 124 | . If the component recognizes the input trace as an LTTng (2.11 or |
| 125 | greater) trace, then it checks specific trace environment values to |
| 126 | build a trace path relative to the directory specified by the |
| 127 | param:path parameter: |
| 128 | + |
| 129 | -- |
| 130 | |
| 131 | Linux kernel domain:: |
| 132 | + |
| 133 | [verse] |
| 134 | __HOST__/__SNAME__-__STIME__/kernel |
| 135 | |
| 136 | User space domain, per-UID buffering:: |
| 137 | + |
| 138 | [verse] |
| 139 | __HOST__/__SNAME__-__STIME__/ust/uid/__UID__/__ARCHW__-bit |
| 140 | |
| 141 | User space domain, per-PID buffering:: |
| 142 | + |
| 143 | [verse] |
| 144 | __HOST__/__SNAME__-__STIME__/ust/pid/__PNAME__-__PID__-__PTIME__ |
| 145 | |
| 146 | -- |
| 147 | + |
| 148 | With: |
| 149 | + |
| 150 | -- |
| 151 | __HOST__:: |
| 152 | Target's hostname. |
| 153 | |
| 154 | __SNAME__:: |
| 155 | Tracing session name. |
| 156 | |
| 157 | __STIME__:: |
| 158 | Tracing session creation date/time. |
| 159 | |
| 160 | __UID__:: |
| 161 | User ID. |
| 162 | |
| 163 | __ARCHW__:: |
| 164 | Architecture's width (`32` or `64`). |
| 165 | |
| 166 | __PNAME__:: |
| 167 | Process name. |
| 168 | |
| 169 | __PID__:: |
| 170 | Process ID. |
| 171 | |
| 172 | __PTIME__:: |
| 173 | Process's date/time. |
| 174 | -- |
| 175 | |
| 176 | . If the input trace has a name, then the component sanitizes this name |
| 177 | and uses it as a relative path to the directory specified by the |
| 178 | param:path parameter. |
| 179 | + |
| 180 | The trace name sanitization operation: |
| 181 | + |
| 182 | * Replaces `.` subdirectories with `_`. |
| 183 | * Replaces `..` subdirectories with `__`. |
| 184 | * Removes any trailing `/` character. |
| 185 | |
| 186 | . The component uses the subdirectory `trace` relative to the directory |
| 187 | specified by the param:path parameter. |
| 188 | |
| 189 | In all the cases above, if the effective output trace path already |
| 190 | exists on the file system, the component appends a numeric suffix to the |
| 191 | name of the last subdirectory. The suffix starts at 0 and increments |
| 192 | until the path does not exist. |
| 193 | |
| 194 | |
| 195 | == INITIALIZATION PARAMETERS |
| 196 | |
| 197 | param:assume-single-trace=`yes` vtype:[optional boolean]:: |
| 198 | Assume that the component only receives messages related to a single |
| 199 | input trace. |
| 200 | + |
| 201 | This parameter affects how the component builds the output trace path |
| 202 | (see <<output-path,``Output path''>>). |
| 203 | |
| 204 | param:ignore-discarded-events=`yes` vtype:[optional boolean]:: |
| 205 | Ignore discarded events messages. |
| 206 | |
| 207 | param:ignore-discarded-packets=`yes` vtype:[optional boolean]:: |
| 208 | Ignore discarded packets messages. |
| 209 | |
| 210 | param:path='PATH' vtype:[string]:: |
| 211 | Base output path. |
| 212 | + |
| 213 | See <<output-path,``Output path''>> to learn how the component uses this |
| 214 | parameter to build the output path for a given input trace. |
| 215 | |
| 216 | param:quiet=`yes` vtype:[optional boolean]:: |
| 217 | Do not write anything to the standard output. |
| 218 | |
| 219 | |
| 220 | == PORTS |
| 221 | |
| 222 | ---- |
| 223 | +-------------+ |
| 224 | | sink.ctf.fs | |
| 225 | | | |
| 226 | @ in | |
| 227 | +-------------+ |
| 228 | ---- |
| 229 | |
| 230 | |
| 231 | === Input |
| 232 | |
| 233 | `in`:: |
| 234 | Single input port. |
| 235 | |
| 236 | |
| 237 | include::common-footer.txt[] |
| 238 | |
| 239 | |
| 240 | == SEE ALSO |
| 241 | |
| 242 | man:babeltrace2-intro(7), |
| 243 | man:babeltrace2-plugin-ctf(7) |