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* Replace PGISOLATIONTIMEOUT with 2 * PG_TEST_TIMEOUT_DEFAULT.Noah Misch2022-07-011-7/+8
| | | | | | Now that the more-generic variable exists, use it. Discussion: https://postgr.es/m/20220219024136.GA3670392@rfd.leadboat.com
* Allow non-quoted identifiers as isolation test session/step names.Tom Lane2021-06-231-6/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | For no obvious reason, isolationtester has always insisted that session and step names be written with double quotes. This is fairly tedious and does little for test readability, especially since the names that people actually choose almost always look like normal identifiers. Hence, let's tweak the lexer to allow SQL-like identifiers not only double-quoted strings. (They're SQL-like, not exactly SQL, because I didn't add any case-folding logic. Also there's no provision for U&"..." names, not that anyone's likely to care.) There is one incompatibility introduced by this change: if you write "foo""bar" with no space, that used to be taken as two identifiers, but now it's just one identifier with an embedded quote mark. I converted all the src/test/isolation/ specfiles to remove unnecessary double quotes, but stopped there because my eyes were glazing over already. Like 741d7f104, back-patch to all supported branches, so that this isn't a stumbling block for back-patching isolation test changes. Discussion: https://postgr.es/m/759113.1623861959@sss.pgh.pa.us
* Use annotations to reduce instability of isolation-test results.Tom Lane2021-06-221-6/+79
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've long contended with isolation test results that aren't entirely stable. Some test scripts insert long delays to try to force stable results, which is not terribly desirable; but other erratic failure modes remain, causing unrepeatable buildfarm failures. I've spent a fair amount of time trying to solve this by improving the server-side support code, without much success: that way is fundamentally unable to cope with diffs that stem from chance ordering of arrival of messages from different server processes. We can improve matters on the client side, however, by annotating the test scripts themselves to show the desired reporting order of events that might occur in different orders. This patch adds three types of annotations to deal with (a) test steps that might or might not complete their waits before the isolationtester can see them waiting; (b) test steps in different sessions that can legitimately complete in either order; and (c) NOTIFY messages that might arrive before or after the completion of a step in another session. We might need more annotation types later, but this seems to be enough to deal with the instabilities we've seen in the buildfarm. It also lets us get rid of all the long delays that were previously used, cutting more than a minute off the runtime of the isolation tests. Back-patch to all supported branches, because the buildfarm instabilities affect all the branches, and because it seems desirable to keep isolationtester's capabilities the same across all branches to simplify possible future back-patching of tests. Discussion: https://postgr.es/m/327948.1623725828@sss.pgh.pa.us
* Fix CREATE INDEX CONCURRENTLY for simultaneous prepared transactions.Noah Misch2021-01-301-3/+3
| | | | | | | | | | | | | | | In a cluster having used CREATE INDEX CONCURRENTLY while having enabled prepared transactions, queries that use the resulting index can silently fail to find rows. Fix this for future CREATE INDEX CONCURRENTLY by making it wait for prepared transactions like it waits for ordinary transactions. This expands the VirtualTransactionId structure domain to admit prepared transactions. It may be necessary to reindex to recover from past occurrences. Back-patch to 9.5 (all supported versions). Andrey Borodin, reviewed (in earlier versions) by Tom Lane and Michael Paquier. Discussion: https://postgr.es/m/2E712143-97F7-4890-B470-4A35142ABC82@yandex-team.ru
* Improve isolationtester's timeout management.Tom Lane2019-12-091-8/+21
| | | | | | | | | | | | | | | | | | | | | | | isolationtester.c had a hard-wired limit of 3 minutes per test step. It now emerges that this isn't quite enough for some of the slowest buildfarm animals. This isn't the first time we've had to raise this limit (cf. 1db439ad4), so let's make it configurable. This patch raises the default to 5 minutes, and introduces an environment variable PGISOLATIONTIMEOUT that can be set if more time is needed, following the precedent of PGCTLTIMEOUT. Also, modify isolationtester so that when the timeout is hit, it explicitly reports having sent a cancel. This makes the regression failure log considerably more intelligible. (In the worst case, a timed-out test might actually be reported as "passing" without this extra output, so arguably this is a bug fix in itself.) In passing, update the README file, which had apparently not gotten touched when we added "make check" support here. Back-patch to 9.6; older versions don't have comparable timeout logic. Discussion: https://postgr.es/m/22964.1575842935@sss.pgh.pa.us
* Raise some timeouts to 180s, in test code.Noah Misch2018-12-101-2/+2
| | | | | | | | | | | | Slow runs of buildfarm members chipmunk, hornet and mandrill saw the shorter timeouts expire. The 180s timeout in poll_query_until has been trouble-free since 2a0f89cd717ce6d49cdc47850577823682167e87 introduced it two years ago, so use 180s more widely. Back-patch to 9.6, where the first of these timeouts was introduced. Reviewed by Michael Paquier. Discussion: https://postgr.es/m/20181209001601.GC2973271@rfd.leadboat.com
* Modify the isolation tester so that multiple sessions can wait.Robert Haas2016-02-111-4/+5
| | | | | | This allows testing of deadlock scenarios. Scenarios that would previously have been considered invalid are now simply taken as a scenario in which more than one backend will wait.
* Rename 'gmake' to 'make' in docs and recommended commandsBruce Momjian2014-02-121-2/+2
| | | | This simplifies the docs and makes it easier to cut/paste command lines.
* Allow isolation tests to specify multiple setup blocks.Kevin Grittner2012-09-041-2/+6
| | | | | | | | | | Each setup block is run as a single PQexec submission, and some statements such as VACUUM cannot be combined with others in such a block. Backpatch to 9.2. Kevin Grittner and Tom Lane
* Update isolation tests' README file.Tom Lane2012-08-081-5/+4
| | | | | The directions explaining about running the prepared-transactions test were not updated in commit ae55d9fbe3871a5e6309d9b91629f1b0ff2b8cba.
* Add simple tests of EvalPlanQual using the isolationtester infrastructure.Tom Lane2012-01-281-29/+60
| | | | | | | | | | | | Much more could be done here, but at least now we have *some* automated test coverage of that mechanism. In particular this tests the writable-CTE case reported by Phil Sorber. In passing, remove isolationtester's arbitrary restriction on the number of steps in a permutation list. I used this so that a single spec file could be used to run several related test scenarios, but there are other possible reasons to want a step series that's not exactly a permutation. Improve documentation and fix a couple other nits as well.
* Explain max_prepared_transactions requirement in isolation tests' README.Tom Lane2011-08-181-5/+10
| | | | | | | | Now that we have a test that requires nondefault settings to pass, it seems like we'd better mention that detail in the directions about how to run the tests. Also do some very minor copy-editing.
* Add support for blocked commands in isolationtesterAlvaro Herrera2011-07-121-0/+13
| | | | | | | | | | | | | This enables us to test that blocking commands (such as foreign keys checks that conflict with some other lock) act as intended. The set of tests that this adds is pretty minimal, but can easily be extended by adding new specs. The intention is that this will serve as a basis for ensuring that further tweaks of locking implementation preserve (or improve) existing behavior. Author: Noah Misch
* Grammar cleanup for src/test/isolation/READMETom Lane2011-05-241-4/+4
| | | | Josh Kupershmidt
* Fix isolation tester Makefile so that it runs in a VPATH buildAlvaro Herrera2011-02-101-1/+1
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* Implement genuine serializable isolation level.Heikki Linnakangas2011-02-081-0/+65
Until now, our Serializable mode has in fact been what's called Snapshot Isolation, which allows some anomalies that could not occur in any serialized ordering of the transactions. This patch fixes that using a method called Serializable Snapshot Isolation, based on research papers by Michael J. Cahill (see README-SSI for full references). In Serializable Snapshot Isolation, transactions run like they do in Snapshot Isolation, but a predicate lock manager observes the reads and writes performed and aborts transactions if it detects that an anomaly might occur. This method produces some false positives, ie. it sometimes aborts transactions even though there is no anomaly. To track reads we implement predicate locking, see storage/lmgr/predicate.c. Whenever a tuple is read, a predicate lock is acquired on the tuple. Shared memory is finite, so when a transaction takes many tuple-level locks on a page, the locks are promoted to a single page-level lock, and further to a single relation level lock if necessary. To lock key values with no matching tuple, a sequential scan always takes a relation-level lock, and an index scan acquires a page-level lock that covers the search key, whether or not there are any matching keys at the moment. A predicate lock doesn't conflict with any regular locks or with another predicate locks in the normal sense. They're only used by the predicate lock manager to detect the danger of anomalies. Only serializable transactions participate in predicate locking, so there should be no extra overhead for for other transactions. Predicate locks can't be released at commit, but must be remembered until all the transactions that overlapped with it have completed. That means that we need to remember an unbounded amount of predicate locks, so we apply a lossy but conservative method of tracking locks for committed transactions. If we run short of shared memory, we overflow to a new "pg_serial" SLRU pool. We don't currently allow Serializable transactions in Hot Standby mode. That would be hard, because even read-only transactions can cause anomalies that wouldn't otherwise occur. Serializable isolation mode now means the new fully serializable level. Repeatable Read gives you the old Snapshot Isolation level that we have always had. Kevin Grittner and Dan Ports, reviewed by Jeff Davis, Heikki Linnakangas and Anssi Kääriäinen