diff --git a/src/test/isolation/isolationtester.c b/src/test/isolation/isolationtester.c
index 126e1856f08689274321aef33f6cc5e064f277a3..96d7f17de8b26762f63f3be45d89839a1c6fee69 100644
--- a/src/test/isolation/isolationtester.c
+++ b/src/test/isolation/isolationtester.c
@@ -21,6 +21,7 @@
#endif
#include "libpq-fe.h"
+#include "pqexpbuffer.h"
#include "isolationtester.h"
@@ -31,7 +32,7 @@
* connections represent spec-defined sessions.
*/
static PGconn **conns = NULL;
-static const char **backend_ids = NULL;
+static const char **backend_pids = NULL;
static int nconns = 0;
static void run_all_permutations(TestSpec * testspec);
@@ -67,6 +68,7 @@ main(int argc, char **argv)
TestSpec *testspec;
int i;
PGresult *res;
+ PQExpBufferData wait_query;
/*
* If the user supplies a parameter on the command line, use it as the
@@ -89,7 +91,7 @@ main(int argc, char **argv)
*/
nconns = 1 + testspec->nsessions;
conns = calloc(nconns, sizeof(PGconn *));
- backend_ids = calloc(nconns, sizeof(*backend_ids));
+ backend_pids = calloc(nconns, sizeof(*backend_pids));
for (i = 0; i < nconns; i++)
{
conns[i] = PQconnectdb(conninfo);
@@ -112,23 +114,22 @@ main(int argc, char **argv)
}
PQclear(res);
- /* Get the backend ID for lock wait checking. */
- res = PQexec(conns[i], "SELECT i FROM pg_stat_get_backend_idset() t(i) "
- "WHERE pg_stat_get_backend_pid(i) = pg_backend_pid()");
+ /* Get the backend pid for lock wait checking. */
+ res = PQexec(conns[i], "SELECT pg_backend_pid()");
if (PQresultStatus(res) == PGRES_TUPLES_OK)
{
if (PQntuples(res) == 1 && PQnfields(res) == 1)
- backend_ids[i] = strdup(PQgetvalue(res, 0, 0));
+ backend_pids[i] = strdup(PQgetvalue(res, 0, 0));
else
{
- fprintf(stderr, "backend id query returned %d rows and %d columns, expected 1 row and 1 column",
+ fprintf(stderr, "backend pid query returned %d rows and %d columns, expected 1 row and 1 column",
PQntuples(res), PQnfields(res));
exit_nicely();
}
}
else
{
- fprintf(stderr, "backend id query failed: %s",
+ fprintf(stderr, "backend pid query failed: %s",
PQerrorMessage(conns[i]));
exit_nicely();
}
@@ -145,8 +146,87 @@ main(int argc, char **argv)
session->steps[stepindex]->session = i;
}
- res = PQprepare(conns[0], PREP_WAITING,
- "SELECT 1 WHERE pg_stat_get_backend_waiting($1)", 0, NULL);
+ /*
+ * Build the query we'll use to detect lock contention among sessions in
+ * the test specification. Most of the time, we could get away with
+ * simply checking whether a session is waiting for *any* lock: we don't
+ * exactly expect concurrent use of test tables. However, autovacuum will
+ * occasionally take AccessExclusiveLock to truncate a table, and we must
+ * ignore that transient wait.
+ */
+ initPQExpBuffer(&wait_query);
+ appendPQExpBufferStr(&wait_query,
+ "SELECT 1 FROM pg_locks holder, pg_locks waiter "
+ "WHERE NOT waiter.granted AND waiter.pid = $1 "
+ "AND holder.granted "
+ "AND holder.pid <> $1 AND holder.pid IN (");
+ /* The spec syntax requires at least one session; assume that here. */
+ appendPQExpBuffer(&wait_query, "%s", backend_pids[1]);
+ for (i = 2; i < nconns; i++)
+ appendPQExpBuffer(&wait_query, ", %s", backend_pids[i]);
+ appendPQExpBufferStr(&wait_query,
+ ") "
+
+ "AND holder.mode = ANY (CASE waiter.mode "
+ "WHEN 'AccessShareLock' THEN ARRAY["
+ "'AccessExclusiveLock'] "
+ "WHEN 'RowShareLock' THEN ARRAY["
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] "
+ "WHEN 'RowExclusiveLock' THEN ARRAY["
+ "'ShareLock',"
+ "'ShareRowExclusiveLock',"
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] "
+ "WHEN 'ShareUpdateExclusiveLock' THEN ARRAY["
+ "'ShareUpdateExclusiveLock',"
+ "'ShareLock',"
+ "'ShareRowExclusiveLock',"
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] "
+ "WHEN 'ShareLock' THEN ARRAY["
+ "'RowExclusiveLock',"
+ "'ShareUpdateExclusiveLock',"
+ "'ShareRowExclusiveLock',"
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] "
+ "WHEN 'ShareRowExclusiveLock' THEN ARRAY["
+ "'RowExclusiveLock',"
+ "'ShareUpdateExclusiveLock',"
+ "'ShareLock',"
+ "'ShareRowExclusiveLock',"
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] "
+ "WHEN 'ExclusiveLock' THEN ARRAY["
+ "'RowShareLock',"
+ "'RowExclusiveLock',"
+ "'ShareUpdateExclusiveLock',"
+ "'ShareLock',"
+ "'ShareRowExclusiveLock',"
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] "
+ "WHEN 'AccessExclusiveLock' THEN ARRAY["
+ "'AccessShareLock',"
+ "'RowShareLock',"
+ "'RowExclusiveLock',"
+ "'ShareUpdateExclusiveLock',"
+ "'ShareLock',"
+ "'ShareRowExclusiveLock',"
+ "'ExclusiveLock',"
+ "'AccessExclusiveLock'] END) "
+
+ "AND holder.locktype IS NOT DISTINCT FROM waiter.locktype "
+ "AND holder.database IS NOT DISTINCT FROM waiter.database "
+ "AND holder.relation IS NOT DISTINCT FROM waiter.relation "
+ "AND holder.page IS NOT DISTINCT FROM waiter.page "
+ "AND holder.tuple IS NOT DISTINCT FROM waiter.tuple "
+ "AND holder.virtualxid IS NOT DISTINCT FROM waiter.virtualxid "
+ "AND holder.transactionid IS NOT DISTINCT FROM waiter.transactionid "
+ "AND holder.classid IS NOT DISTINCT FROM waiter.classid "
+ "AND holder.objid IS NOT DISTINCT FROM waiter.objid "
+ "AND holder.objsubid IS NOT DISTINCT FROM waiter.objsubid ");
+
+ res = PQprepare(conns[0], PREP_WAITING, wait_query.data, 0, NULL);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
fprintf(stderr, "prepare of lock wait query failed: %s",
@@ -154,6 +234,7 @@ main(int argc, char **argv)
exit_nicely();
}
PQclear(res);
+ termPQExpBuffer(&wait_query);
/*
* Run the permutations specified in the spec, or all if none were
@@ -411,9 +492,7 @@ run_permutation(TestSpec * testspec, int nsteps, Step ** steps)
* Our caller already sent the query associated with this step. Wait for it
* to either complete or (if given the STEP_NONBLOCK flag) to block while
* waiting for a lock. We assume that any lock wait will persist until we
- * have executed additional steps in the permutation. This is not fully
- * robust -- a concurrent autovacuum could briefly take a lock with which we
- * conflict. The risk may be low enough to discount.
+ * have executed additional steps in the permutation.
*
* When calling this function on behalf of a given step for a second or later
* time, pass the STEP_RETRY flag. This only affects the messages printed.
@@ -450,7 +529,7 @@ try_complete_step(Step *step, int flags)
int ntuples;
res = PQexecPrepared(conns[0], PREP_WAITING, 1,
- &backend_ids[step->session + 1],
+ &backend_pids[step->session + 1],
NULL, NULL, 0);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{