TEXT format was tricky due to its inconsistencies, but I think I have
something working reasonably well. I added a simple test for TEXT
format output as well, using a similar approach as the JSON format
test, and liberally regexp_replacing away any volatile output. I
suppose in theory we could do this for YAML, too, but I think it's
gross enough not to be worth it, especially given the high similarity
of all the structured outputs.
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index d189b8d573..c3c27e13a1 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -100,7 +100,7 @@ static void show_sortorder_options(StringInfo buf, Node *sortexpr,
Oid sortOperator, Oid collation, bool nullsFirst);
static void show_tablesample(TableSampleClause *tsc, PlanState *planstate,
List *ancestors, ExplainState *es);
-static void show_sort_info(SortState *sortstate, ExplainState *es);
+static void show_sort_info(SortState *sortstate, StringInfo* worker_strs, ExplainState *es);
static void show_hash_info(HashState *hashstate, ExplainState *es);
static void show_tidbitmap_info(BitmapHeapScanState *planstate,
ExplainState *es);
@@ -289,6 +289,7 @@ NewExplainState(void)
es->costs = true;
/* Prepare output buffer. */
es->str = makeStringInfo();
+ es->root_str = es->str;
return es;
}
@@ -1090,9 +1091,20 @@ ExplainNode(PlanState *planstate, List *ancestors,
const char *partialmode = NULL;
const char *operation = NULL;
const char *custom_name = NULL;
+ StringInfo *worker_strs = NULL;
int save_indent = es->indent;
bool haschildren;
+ /* Prepare per-worker output */
+ if (es->analyze && planstate->worker_instrument) {
+ int num_workers = planstate->worker_instrument->num_workers;
+ int n;
+ worker_strs = (StringInfo *) palloc0(num_workers * sizeof(StringInfo));
+ for (n = 0; n < num_workers; n++) {
+ worker_strs[n] = makeStringInfo();
+ }
+ }
+
switch (nodeTag(plan))
{
case T_Result:
@@ -1357,6 +1369,58 @@ ExplainNode(PlanState *planstate, List *ancestors,
ExplainPropertyBool("Parallel Aware", plan->parallel_aware, es);
}
+ /* Prepare worker general execution details */
+ if (es->analyze && es->verbose && planstate->worker_instrument)
+ {
+ WorkerInstrumentation *w = planstate->worker_instrument;
+ int n;
+
+ for (n = 0; n < w->num_workers; ++n)
+ {
+ Instrumentation *instrument = &w->instrument[n];
+ double nloops = instrument->nloops;
+ double startup_ms;
+ double total_ms;
+ double rows;
+
+ if (nloops <= 0)
+ continue;
+ startup_ms = 1000.0 * instrument->startup / nloops;
+ total_ms = 1000.0 * instrument->total / nloops;
+ rows = instrument->ntuples / nloops;
+
+ ExplainOpenWorker(worker_strs[n], es);
+
+ if (es->format == EXPLAIN_FORMAT_TEXT)
+ {
+ if (es->timing)
+ appendStringInfo(es->str,
+ "actual time=%.3f..%.3f rows=%.0f loops=%.0f\n",
+ startup_ms, total_ms, rows, nloops);
+ else
+ appendStringInfo(es->str,
+ "actual rows=%.0f loops=%.0f\n",
+ rows, nloops);
+ if (es->buffers)
+ show_buffer_usage(es, &instrument->bufusage);
+ }
+ else
+ {
+ if (es->timing)
+ {
+ ExplainPropertyFloat("Actual Startup Time", "ms",
+ startup_ms, 3, es);
+ ExplainPropertyFloat("Actual Total Time", "ms",
+ total_ms, 3, es);
+ }
+ ExplainPropertyFloat("Actual Rows", NULL, rows, 0, es);
+ ExplainPropertyFloat("Actual Loops", NULL, nloops, 0, es);
+ }
+ }
+
+ ExplainCloseWorker(es);
+ }
+
switch (nodeTag(plan))
{
case T_SeqScan:
@@ -1856,7 +1920,7 @@ ExplainNode(PlanState *planstate, List *ancestors,
break;
case T_Sort:
show_sort_keys(castNode(SortState, planstate), ancestors, es);
- show_sort_info(castNode(SortState, planstate), es);
+ show_sort_info(castNode(SortState, planstate), worker_strs, es);
break;
case T_MergeAppend:
show_merge_append_keys(castNode(MergeAppendState, planstate),
@@ -1885,74 +1949,30 @@ ExplainNode(PlanState *planstate, List *ancestors,
if (es->buffers && planstate->instrument)
show_buffer_usage(es, &planstate->instrument->bufusage);
- /* Show worker detail */
- if (es->analyze && es->verbose && !es->hide_workers &&
- planstate->worker_instrument)
+ /* Prepare worker buffer usage */
+ if (es->buffers && es->analyze && es->verbose && !es->hide_workers
+ && planstate->worker_instrument && es->format != EXPLAIN_FORMAT_TEXT)
{
WorkerInstrumentation *w = planstate->worker_instrument;
- bool opened_group = false;
int n;
for (n = 0; n < w->num_workers; ++n)
{
Instrumentation *instrument = &w->instrument[n];
double nloops = instrument->nloops;
- double startup_ms;
- double total_ms;
- double rows;
if (nloops <= 0)
continue;
- startup_ms = 1000.0 * instrument->startup / nloops;
- total_ms = 1000.0 * instrument->total / nloops;
- rows = instrument->ntuples / nloops;
-
- if (es->format == EXPLAIN_FORMAT_TEXT)
- {
- appendStringInfoSpaces(es->str, es->indent * 2);
- appendStringInfo(es->str, "Worker %d: ", n);
- if (es->timing)
- appendStringInfo(es->str,
- "actual time=%.3f..%.3f rows=%.0f loops=%.0f\n",
- startup_ms, total_ms, rows, nloops);
- else
- appendStringInfo(es->str,
- "actual rows=%.0f loops=%.0f\n",
- rows, nloops);
- es->indent++;
- if (es->buffers)
- show_buffer_usage(es, &instrument->bufusage);
- es->indent--;
- }
- else
- {
- if (!opened_group)
- {
- ExplainOpenGroup("Workers", "Workers", false, es);
- opened_group = true;
- }
- ExplainOpenGroup("Worker", NULL, true, es);
- ExplainPropertyInteger("Worker Number", NULL, n, es);
- if (es->timing)
- {
- ExplainPropertyFloat("Actual Startup Time", "ms",
- startup_ms, 3, es);
- ExplainPropertyFloat("Actual Total Time", "ms",
- total_ms, 3, es);
- }
- ExplainPropertyFloat("Actual Rows", NULL, rows, 0, es);
- ExplainPropertyFloat("Actual Loops", NULL, nloops, 0, es);
-
- if (es->buffers)
- show_buffer_usage(es, &instrument->bufusage);
-
- ExplainCloseGroup("Worker", NULL, true, es);
- }
+ ExplainOpenWorker(worker_strs[n], es);
+ show_buffer_usage(es, &instrument->bufusage);
}
+ ExplainCloseWorker(es);
+ }
- if (opened_group)
- ExplainCloseGroup("Workers", "Workers", false, es);
+ /* Show worker detail */
+ if (planstate->worker_instrument) {
+ ExplainFlushWorkers(worker_strs, planstate->worker_instrument->num_workers, es);
}
/* Get ready to display the child plans */
@@ -2552,7 +2572,7 @@ show_tablesample(TableSampleClause *tsc, PlanState *planstate,
* If it's EXPLAIN ANALYZE, show tuplesort stats for a sort node
*/
static void
-show_sort_info(SortState *sortstate, ExplainState *es)
+show_sort_info(SortState *sortstate, StringInfo *worker_strs, ExplainState *es)
{
if (!es->analyze)
return;
@@ -2593,7 +2613,7 @@ show_sort_info(SortState *sortstate, ExplainState *es)
if (sortstate->shared_info != NULL)
{
int n;
- bool opened_group = false;
+ bool indent = es->print_workers;
for (n = 0; n < sortstate->shared_info->num_workers; n++)
{
@@ -2609,32 +2629,26 @@ show_sort_info(SortState *sortstate, ExplainState *es)
spaceType = tuplesort_space_type_name(sinstrument->spaceType);
spaceUsed = sinstrument->spaceUsed;
+ ExplainOpenWorker(worker_strs[n], es);
+
if (es->format == EXPLAIN_FORMAT_TEXT)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
- if (n > 0 || !es->hide_workers)
- appendStringInfo(es->str, "Worker %d: ", n);
+ if (indent)
+ {
+ appendStringInfoSpaces(es->str, es->indent * 2);
+ }
appendStringInfo(es->str,
"Sort Method: %s %s: %ldkB\n",
sortMethod, spaceType, spaceUsed);
}
else
{
- if (!opened_group)
- {
- ExplainOpenGroup("Workers", "Workers", false, es);
- opened_group = true;
- }
- ExplainOpenGroup("Worker", NULL, true, es);
- ExplainPropertyInteger("Worker Number", NULL, n, es);
ExplainPropertyText("Sort Method", sortMethod, es);
ExplainPropertyInteger("Sort Space Used", "kB", spaceUsed, es);
ExplainPropertyText("Sort Space Type", spaceType, es);
- ExplainCloseGroup("Worker", NULL, true, es);
}
}
- if (opened_group)
- ExplainCloseGroup("Workers", "Workers", false, es);
+ ExplainCloseWorker(es);
}
}
@@ -3751,6 +3765,75 @@ ExplainCloseGroup(const char *objtype, const char *labelname,
}
}
+/*
+ * Begin output for a specific worker. If we are currently producing output
+ * for another worker, close that worker automatically.
+ */
+void
+ExplainOpenWorker(StringInfo worker_str, ExplainState *es)
+{
+ /*
+ * For structured formats, we indent twice--once for the "Worker" group
+ * and once for the "Workers" group--but only need to adjust indentation
+ * once for each string of ExplainOpenWorker calls. For text format, we
+ * just indent once, to add worker info on the next worker line.
+ */
+ if (es->str == es->root_str)
+ {
+ es->indent += es->format == EXPLAIN_FORMAT_TEXT ? 1 : 2;
+ }
+
+ es->print_workers = true;
+ es->str = worker_str;
+}
+
+/*
+ * Explicitly end output for the current worker and resume output
+ * for the root of the node.
+ */
+void
+ExplainCloseWorker(ExplainState *es)
+{
+ /* as above, the text format has different indentation */
+ es->indent -= es->format == EXPLAIN_FORMAT_TEXT ? 1 : 2;
+
+ es->str = es->root_str;
+}
+
+/*
+ * Flush output registered so far to the output buffer and deallocate
+ * mechanism for writing to workers.
+ */
+void
+ExplainFlushWorkers(StringInfo* worker_strs, int num_workers, ExplainState *es)
+{
+ int i;
+
+ if (!es->print_workers) {
+ return;
+ }
+
+ ExplainOpenGroup("Workers", "Workers", false, es);
+ for (i = 0; i < num_workers; i++) {
+ ExplainOpenGroup("Worker", NULL, true, es);
+ if (es->format == EXPLAIN_FORMAT_TEXT)
+ {
+ appendStringInfoSpaces(es->str, es->indent * 2);
+ appendStringInfo(es->str, "Worker %d: ", i);
+ }
+ else
+ {
+ ExplainPropertyInteger("Worker Number", NULL, i, es);
+ }
+
+ appendStringInfoString(es->str, worker_strs[i]->data);
+ ExplainCloseGroup("Worker", NULL, true, es);
+ }
+ ExplainCloseGroup("Workers", "Workers", false, es);
+ // do we have any other cleanup to do?
+ es->print_workers = false;
+}
+
/*
* Emit a "dummy" group that never has any members.
*
diff --git a/src/include/commands/explain.h b/src/include/commands/explain.h
index 45027a7c47..2919b2780d 100644
--- a/src/include/commands/explain.h
+++ b/src/include/commands/explain.h
@@ -27,7 +27,7 @@ typedef enum ExplainFormat
typedef struct ExplainState
{
- StringInfo str; /* output buffer */
+ StringInfo str; /* current output buffer */
/* options */
bool verbose; /* be verbose */
bool analyze; /* print actual times */
@@ -40,6 +40,8 @@ typedef struct ExplainState
/* state for output formatting --- not reset for each new plan tree */
int indent; /* current indentation level */
List *grouping_stack; /* format-specific grouping state */
+ bool print_workers; /* whether current node has worker metadata */
+ StringInfo root_str; /* root output buffer */
/* state related to the current plan tree (filled by ExplainPrintPlan) */
PlannedStmt *pstmt; /* top of plan */
List *rtable; /* range table */
@@ -111,4 +113,9 @@ extern void ExplainOpenGroup(const char *objtype, const char *labelname,
extern void ExplainCloseGroup(const char *objtype, const char *labelname,
bool labeled, ExplainState *es);
+extern void ExplainOpenWorker(StringInfo worker_str, ExplainState *es);
+extern void ExplainCloseWorker(ExplainState *es);
+extern void ExplainFlushWorkers(StringInfo *worker_strs, int num_workers, ExplainState *es);
+
+
#endif /* EXPLAIN_H */
diff --git a/src/test/regress/expected/explain.out b/src/test/regress/expected/explain.out
new file mode 100644
index 0000000000..8034a4e0db
--- /dev/null
+++ b/src/test/regress/expected/explain.out
@@ -0,0 +1,114 @@
+--
+-- EXPLAIN
+--
+-- helper functions for examining explain output
+-- return a json explain of given query
+CREATE OR REPLACE FUNCTION json_explain(query text, variadic opts text[])
+ RETURNS json LANGUAGE PLPGSQL AS $$
+DECLARE
+ plan json;
+BEGIN
+ EXECUTE 'EXPLAIN (' || array_to_string(array_append(opts, 'FORMAT JSON) '), ', ') || query INTO STRICT plan;
+ RETURN plan;
+END;
+$$;
+-- return a text explain of given query
+CREATE OR REPLACE FUNCTION text_explain(query text, variadic opts text[])
+ RETURNS text LANGUAGE PLPGSQL AS $$
+DECLARE
+ plan_row RECORD;
+ plan text = '';
+BEGIN
+ FOR plan_row IN EXECUTE 'EXPLAIN (' || array_to_string(array_append(opts, 'FORMAT TEXT) '), ', ') || query LOOP
+ plan = plan || plan_row."QUERY PLAN" || E'\n';
+ END LOOP;
+
+ RETURN plan;
+END;
+$$;
+/*
+ * Takes a json object and processes its keys and values. For every
+ * matching key whose value is a number, set it to zero to facilitate
+ * comparisons for values that can vary across executions. If not a number,
+ * set the value to -1 to indicate we matched an unexpected key. Return
+ * non-matching keys and values unmodified.
+ */
+CREATE OR REPLACE FUNCTION json_normalize_numeric_keys_matching(obj json, regexp text)
+ RETURNS json LANGUAGE SQL AS $$
+SELECT
+ coalesce(json_object_agg(
+ key,
+ CASE
+ WHEN key ~ regexp THEN
+ CASE json_typeof(value)
+ WHEN 'number' THEN 0::text::json
+ ELSE (-1)::text::json
+ END
+ ELSE value
+ END
+ ), '{}')
+FROM
+ json_each(obj)
+$$;
+-- explain only worker information, normalizing any values that could vary across executions
+CREATE OR REPLACE FUNCTION explain_workers(plan_node json)
+ RETURNS json LANGUAGE SQL AS $$
+SELECT
+ coalesce(json_object_agg(key, value), '{}')
+FROM (
+ SELECT
+ key,
+ CASE key
+ WHEN 'Workers' THEN
+ (SELECT json_agg(
+ json_normalize_numeric_keys_matching(worker, '(Blocks|Time)$|Sort Space Used')
+ )
+ FROM json_array_elements(value) AS workers(worker))
+ WHEN 'Plans' THEN
+ (SELECT json_agg(
+ explain_workers(child)
+ )
+ FROM json_array_elements(value) AS children(child))
+ END AS value
+ FROM
+ json_each(plan_node) AS entries(key, value)
+ WHERE
+ key IN ('Workers', 'Plans')
+) AS plan_fields(key, value);
+$$;
+-- test that per-worker sort and buffers output is combined correctly in EXPLAIN
+set force_parallel_mode = true;
+SELECT explain_workers(json_explain($$
+ SELECT * FROM (VALUES(1),(2)) x ORDER BY x;
+$$, 'verbose', 'analyze', 'buffers') -> 0 -> 'Plan');
+ explain_workers
+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ { "Plans" : [{ "Workers" : [{ "Worker Number" : 0, "Actual Startup Time" : 0, "Actual Total Time" : 0, "Actual Rows" : 2, "Actual Loops" : 1, "Sort Method" : "quicksort", "Sort Space Used" : 0, "Sort Space Type" : "Memory", "Shared Hit Blocks" : 0, "Shared Read Blocks" : 0, "Shared Dirtied Blocks" : 0, "Shared Written Blocks" : 0, "Local Hit Blocks" : 0, "Local Read Blocks" : 0, "Local Dirtied Blocks" : 0, "Local Written Blocks" : 0, "Temp Read Blocks" : 0, "Temp Written Blocks" : 0 }], "Plans" : [{ "Workers" : [{ "Worker Number" : 0, "Actual Startup Time" : 0, "Actual Total Time" : 0, "Actual Rows" : 2, "Actual Loops" : 1, "Shared Hit Blocks" : 0, "Shared Read Blocks" : 0, "Shared Dirtied Blocks" : 0, "Shared Written Blocks" : 0, "Local Hit Blocks" : 0, "Local Read Blocks" : 0, "Local Dirtied Blocks" : 0, "Local Written Blocks" : 0, "Temp Read Blocks" : 0, "Temp Written Blocks" : 0 }] }] }] }
+(1 row)
+
+SELECT regexp_replace(regexp_replace(text_explain($$
+ SELECT * FROM (VALUES(1),(2)) x ORDER BY x;
+$$, 'verbose', 'analyze', 'buffers', 'timing off', 'costs off', 'summary off'),
+ 'Buffers: .+?$', 'Buffers: xxx', 'n'), 'Sort Method: .+?$', 'Sort Method: xxx', 'n');
+ regexp_replace
+-------------------------------------------------------------------
+ Gather (actual rows=2 loops=1) +
+ Output: "*VALUES*".column1, (ROW("*VALUES*".column1)) +
+ Workers Planned: 1 +
+ Workers Launched: 1 +
+ Single Copy: true +
+ Buffers: xxx +
+ -> Sort (actual rows=2 loops=1) +
+ Output: "*VALUES*".column1, (ROW("*VALUES*".column1)) +
+ Sort Key: (ROW("*VALUES*".column1)) +
+ Buffers: shared hit=114 +
+ Worker 0: actual rows=2 loops=1 +
+ Buffers: shared hit=114 +
+ Sort Method: xxx +
+ -> Values Scan on "*VALUES*" (actual rows=2 loops=1) +
+ Output: "*VALUES*".column1, ROW("*VALUES*".column1)+
+ Worker 0: actual rows=2 loops=1 +
+
+(1 row)
+
+reset force_parallel_mode;
diff --git a/src/test/regress/expected/select_parallel.out b/src/test/regress/expected/select_parallel.out
index 96dfb7c8dd..cba15f7133 100644
--- a/src/test/regress/expected/select_parallel.out
+++ b/src/test/regress/expected/select_parallel.out
@@ -591,10 +591,10 @@ select * from explain_parallel_sort_stats();
-> Sort (actual rows=2000 loops=15)
Sort Key: tenk1.ten
Sort Method: quicksort Memory: xxx
- Worker 0: Sort Method: quicksort Memory: xxx
- Worker 1: Sort Method: quicksort Memory: xxx
- Worker 2: Sort Method: quicksort Memory: xxx
- Worker 3: Sort Method: quicksort Memory: xxx
+ Worker 0: Sort Method: quicksort Memory: xxx
+ Worker 1: Sort Method: quicksort Memory: xxx
+ Worker 2: Sort Method: quicksort Memory: xxx
+ Worker 3: Sort Method: quicksort Memory: xxx
-> Parallel Seq Scan on tenk1 (actual rows=2000 loops=15)
Filter: (ten < 100)
(14 rows)
diff --git a/src/test/regress/parallel_schedule b/src/test/regress/parallel_schedule
index d33a4e143d..d2b17dd3ea 100644
--- a/src/test/regress/parallel_schedule
+++ b/src/test/regress/parallel_schedule
@@ -112,7 +112,7 @@ test: plancache limit plpgsql copy2 temp domain rangefuncs prepare conversion tr
# ----------
# Another group of parallel tests
# ----------
-test: partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort
+test: partition_join partition_prune reloptions hash_part indexing partition_aggregate partition_info tuplesort explain
# event triggers cannot run concurrently with any test that runs DDL
test: event_trigger
diff --git a/src/test/regress/serial_schedule b/src/test/regress/serial_schedule
index f86f5c5682..acba391332 100644
--- a/src/test/regress/serial_schedule
+++ b/src/test/regress/serial_schedule
@@ -193,6 +193,7 @@ test: indexing
test: partition_aggregate
test: partition_info
test: tuplesort
+test: explain
test: event_trigger
test: fast_default
test: stats
diff --git a/src/test/regress/sql/explain.sql b/src/test/regress/sql/explain.sql
new file mode 100644
index 0000000000..03accb1b83
--- /dev/null
+++ b/src/test/regress/sql/explain.sql
@@ -0,0 +1,98 @@
+--
+-- EXPLAIN
+--
+
+-- helper functions for examining explain output
+
+-- return a json explain of given query
+CREATE OR REPLACE FUNCTION json_explain(query text, variadic opts text[])
+ RETURNS json LANGUAGE PLPGSQL AS $$
+DECLARE
+ plan json;
+BEGIN
+ EXECUTE 'EXPLAIN (' || array_to_string(array_append(opts, 'FORMAT JSON) '), ', ') || query INTO STRICT plan;
+ RETURN plan;
+END;
+$$;
+
+-- return a text explain of given query
+CREATE OR REPLACE FUNCTION text_explain(query text, variadic opts text[])
+ RETURNS text LANGUAGE PLPGSQL AS $$
+DECLARE
+ plan_row RECORD;
+ plan text = '';
+BEGIN
+ FOR plan_row IN EXECUTE 'EXPLAIN (' || array_to_string(array_append(opts, 'FORMAT TEXT) '), ', ') || query LOOP
+ plan = plan || plan_row."QUERY PLAN" || E'\n';
+ END LOOP;
+
+ RETURN plan;
+END;
+$$;
+
+
+/*
+ * Takes a json object and processes its keys and values. For every
+ * matching key whose value is a number, set it to zero to facilitate
+ * comparisons for values that can vary across executions. If not a number,
+ * set the value to -1 to indicate we matched an unexpected key. Return
+ * non-matching keys and values unmodified.
+ */
+CREATE OR REPLACE FUNCTION json_normalize_numeric_keys_matching(obj json, regexp text)
+ RETURNS json LANGUAGE SQL AS $$
+SELECT
+ coalesce(json_object_agg(
+ key,
+ CASE
+ WHEN key ~ regexp THEN
+ CASE json_typeof(value)
+ WHEN 'number' THEN 0::text::json
+ ELSE (-1)::text::json
+ END
+ ELSE value
+ END
+ ), '{}')
+FROM
+ json_each(obj)
+$$;
+
+-- explain only worker information, normalizing any values that could vary across executions
+CREATE OR REPLACE FUNCTION explain_workers(plan_node json)
+ RETURNS json LANGUAGE SQL AS $$
+SELECT
+ coalesce(json_object_agg(key, value), '{}')
+FROM (
+ SELECT
+ key,
+ CASE key
+ WHEN 'Workers' THEN
+ (SELECT json_agg(
+ json_normalize_numeric_keys_matching(worker, '(Blocks|Time)$|Sort Space Used')
+ )
+ FROM json_array_elements(value) AS workers(worker))
+ WHEN 'Plans' THEN
+ (SELECT json_agg(
+ explain_workers(child)
+ )
+ FROM json_array_elements(value) AS children(child))
+ END AS value
+ FROM
+ json_each(plan_node) AS entries(key, value)
+ WHERE
+ key IN ('Workers', 'Plans')
+) AS plan_fields(key, value);
+$$;
+
+-- test that per-worker sort and buffers output is combined correctly in EXPLAIN
+set force_parallel_mode = true;
+
+SELECT explain_workers(json_explain($$
+ SELECT * FROM (VALUES(1),(2)) x ORDER BY x;
+$$, 'verbose', 'analyze', 'buffers') -> 0 -> 'Plan');
+
+SELECT regexp_replace(regexp_replace(text_explain($$
+ SELECT * FROM (VALUES(1),(2)) x ORDER BY x;
+$$, 'verbose', 'analyze', 'buffers', 'timing off', 'costs off', 'summary off'),
+ 'Buffers: .+?$', 'Buffers: xxx', 'n'), 'Sort Method: .+?$', 'Sort Method: xxx', 'n');
+
+reset force_parallel_mode;
