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+[[trials]]
+== Trial: Binaries to be Tested
+
+A trial is a set of pre-built binaries to be tested. They are typically built
+by jenkins using the build scripts found in osmo-gsm-tester's source in the
+'contrib/' dir.
+
+A trial comes in the form of a directory containing a number of '*.tgz' tar
+archives as well as a 'checksums.md5' file to verify the tar archives'
+integrity.
+
+When the osmo-gsm-tester is invoked to run on such a trial directory, it will
+create a sub directory named 'inst' and unpack the tar archives into it.
+
+For each test run on this trial, a new subdirectory in the trial dir is
+created, named in the form of 'run.<timestamp>'. A symbolic link 'last-run'
+will point at the most recently created run dir. This run dir will accumulate
+the rendered configuration files used for the trial run as well as a test log
+(<- *TODO*) and stdout and stderr outputs of the binaries run for the trial.
+(*TODO*->) When the test is complete, jenkins parsable XML reports for the test
+run will be written to the 'run.<timestamp>' subdir.