30. Regression Tests
The regression tests are a comprehensive set of tests for the SQL implementation in PostgreSQL™. They test standard SQL operations as well as the extended capabilities of PostgreSQL™.
30.1. Running the Tests
The regression tests can be run against an already installed and running server, or using a temporary installation within the build tree. Furthermore, there is a «parallel» and a «sequential» mode for running the tests. The sequential method runs each test script alone, while the parallel method starts up multiple server processes to run groups of tests in parallel. Parallel testing gives confidence that interprocess communication and locking are working correctly.
To run the parallel regression tests after building but before installation, type:
in the top-level directory. (Or you can change to src/test/regress and run the command there.) This will first build several auxiliary files, such as sample user-defined trigger functions, and then run the test driver script. At the end you should see something like:
======================= All 115 tests passed. =======================
or otherwise a note about which tests failed. See Sezione 30.2, «Test Evaluation» below before assuming that a «failure» represents a serious problem.
Because this test method runs a temporary server, it will not work when you are the root user (since the server will not start as root). If you already did the build as root, you do not have to start all over. Instead, make the regression test directory writable by some other user, log in as that user, and restart the tests. For example:
root# chmod -R a+w src/test/regress root# su - joeuser joeuser$ cd top-level build directory joeuser$ gmake check
(The only possible «security risk» here is that other users might be able to alter the regression test results behind your back. Use common sense when managing user permissions.)
Alternatively, run the tests after installation.
If you have configured PostgreSQL™ to install into a location where an older PostgreSQL™ installation already exists, and you perform gmake check before installing the new version, you might find that the tests fail because the new programs try to use the already-installed shared libraries. (Typical symptoms are complaints about undefined symbols.) If you wish to run the tests before overwriting the old installation, you'll need to build with configure --disable-rpath. It is not recommended that you use this option for the final installation, however.
The parallel regression test starts quite a few processes under your user ID. Presently, the maximum concurrency is twenty parallel test scripts, which means forty processes: there's a server process and a psql process for each test script. So if your system enforces a per-user limit on the number of processes, make sure this limit is at least fifty or so, else you might get random-seeming failures in the parallel test. If you are not in a position to raise the limit, you can cut down the degree of parallelism by setting the MAX_CONNECTIONS parameter. For example:
gmake MAX_CONNECTIONS=10 check
runs no more than ten tests concurrently.
To run the tests after installation (see Capitolo 15, Installation from Source Code), initialize a data area and start the server, as explained in Capitolo 17, Setup e operatività del server then type:
or for a parallel test:
The tests will expect to contact the server at the local host and the default port number, unless directed otherwise by PGHOST and PGPORT environment variables.
The source distribution also contains regression tests for the optional procedural languages and for some of the contrib modules. At present, these tests can be used only against an already-installed server. To run the tests for all procedural languages that have been built and installed, change to the src/pl directory of the build tree and type:
You can also do this in any of the subdirectories of src/pl to run tests for just one procedural language. To run the tests for all contrib modules that have them, change to the contrib directory of the build tree and type:
The contrib modules must have been built and installed first. You can also do this in a subdirectory of contrib to run the tests for just one module.
The source distribution also contains regression tests of the static behaviour of Hot Standby. These tests require a running primary server and a running standby server that is accepting new WAL changes from the primary using either file-based log shipping or streaming replication. Those servers are not automatically created for you, nor is the setup documented here. Please check the various sections of the docs already devoted to the required commands and related issues.
First create a database called "regression" on the primary.
psql -h primary -c "CREATE DATABASE regression"
Next, run a preparatory script on the primary in the regression database: src/test/regress/sql/hs_primary_setup.sql, and allow for the changes to propagate to the standby, for example
psql -h primary -f src/test/regress/sql/hs_primary_setup.sql regression
Now confirm that the default connection for the tester is the standby server under test and then run the standbycheck target from the regression directory:
cd src/test/regress gmake standbycheck
Some extreme behaviours can also be generated on the primary using the script: src/test/regress/sql/hs_primary_extremes.sql to allow the behaviour of the standby to be tested.
Additional automated testing may be available in later releases.