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-rw-r--r--src/backend/commands/explain.c544
1 files changed, 417 insertions, 127 deletions
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index d189b8d573a..f523adbc726 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -57,6 +57,8 @@ static void ExplainOneQuery(Query *query, int cursorOptions,
IntoClause *into, ExplainState *es,
const char *queryString, ParamListInfo params,
QueryEnvironment *queryEnv);
+static void ExplainPrintJIT(ExplainState *es, int jit_flags,
+ JitInstrumentation *ji);
static void report_triggers(ResultRelInfo *rInfo, bool show_relname,
ExplainState *es);
static double elapsed_time(instr_time *starttime);
@@ -123,11 +125,20 @@ static void ExplainSubPlans(List *plans, List *ancestors,
const char *relationship, ExplainState *es);
static void ExplainCustomChildren(CustomScanState *css,
List *ancestors, ExplainState *es);
+static ExplainWorkersState *ExplainCreateWorkersState(int num_workers);
+static void ExplainOpenWorker(int n, ExplainState *es);
+static void ExplainCloseWorker(int n, ExplainState *es);
+static void ExplainFlushWorkersState(ExplainState *es);
static void ExplainProperty(const char *qlabel, const char *unit,
const char *value, bool numeric, ExplainState *es);
+static void ExplainOpenSetAsideGroup(const char *objtype, const char *labelname,
+ bool labeled, int depth, ExplainState *es);
+static void ExplainSaveGroup(ExplainState *es, int depth, int *state_save);
+static void ExplainRestoreGroup(ExplainState *es, int depth, int *state_save);
static void ExplainDummyGroup(const char *objtype, const char *labelname,
ExplainState *es);
static void ExplainXMLTag(const char *tagname, int flags, ExplainState *es);
+static void ExplainIndentText(ExplainState *es);
static void ExplainJSONLineEnding(ExplainState *es);
static void ExplainYAMLLineStarting(ExplainState *es);
static void escape_yaml(StringInfo buf, const char *str);
@@ -790,31 +801,22 @@ ExplainPrintJITSummary(ExplainState *es, QueryDesc *queryDesc)
if (queryDesc->estate->es_jit_worker_instr)
InstrJitAgg(&ji, queryDesc->estate->es_jit_worker_instr);
- ExplainPrintJIT(es, queryDesc->estate->es_jit_flags, &ji, -1);
+ ExplainPrintJIT(es, queryDesc->estate->es_jit_flags, &ji);
}
/*
* ExplainPrintJIT -
* Append information about JITing to es->str.
- *
- * Can be used to print the JIT instrumentation of the backend (worker_num =
- * -1) or that of a specific worker (worker_num = ...).
*/
-void
-ExplainPrintJIT(ExplainState *es, int jit_flags,
- JitInstrumentation *ji, int worker_num)
+static void
+ExplainPrintJIT(ExplainState *es, int jit_flags, JitInstrumentation *ji)
{
instr_time total_time;
- bool for_workers = (worker_num >= 0);
/* don't print information if no JITing happened */
if (!ji || ji->created_functions == 0)
return;
- /* don't print per-worker info if we're supposed to hide that */
- if (for_workers && es->hide_workers)
- return;
-
/* calculate total time */
INSTR_TIME_SET_ZERO(total_time);
INSTR_TIME_ADD(total_time, ji->generation_counter);
@@ -827,16 +829,13 @@ ExplainPrintJIT(ExplainState *es, int jit_flags,
/* for higher density, open code the text output format */
if (es->format == EXPLAIN_FORMAT_TEXT)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
- if (for_workers)
- appendStringInfo(es->str, "JIT for worker %u:\n", worker_num);
- else
- appendStringInfoString(es->str, "JIT:\n");
- es->indent += 1;
+ ExplainIndentText(es);
+ appendStringInfoString(es->str, "JIT:\n");
+ es->indent++;
ExplainPropertyInteger("Functions", NULL, ji->created_functions, es);
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str, "Options: %s %s, %s %s, %s %s, %s %s\n",
"Inlining", jit_flags & PGJIT_INLINE ? "true" : "false",
"Optimization", jit_flags & PGJIT_OPT3 ? "true" : "false",
@@ -845,7 +844,7 @@ ExplainPrintJIT(ExplainState *es, int jit_flags,
if (es->analyze && es->timing)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str,
"Timing: %s %.3f ms, %s %.3f ms, %s %.3f ms, %s %.3f ms, %s %.3f ms\n",
"Generation", 1000.0 * INSTR_TIME_GET_DOUBLE(ji->generation_counter),
@@ -855,11 +854,10 @@ ExplainPrintJIT(ExplainState *es, int jit_flags,
"Total", 1000.0 * INSTR_TIME_GET_DOUBLE(total_time));
}
- es->indent -= 1;
+ es->indent--;
}
else
{
- ExplainPropertyInteger("Worker Number", NULL, worker_num, es);
ExplainPropertyInteger("Functions", NULL, ji->created_functions, es);
ExplainOpenGroup("Options", "Options", true, es);
@@ -1074,9 +1072,10 @@ ExplainPreScanNode(PlanState *planstate, Bitmapset **rels_used)
* optional name to be attached to the node.
*
* In text format, es->indent is controlled in this function since we only
- * want it to change at plan-node boundaries. In non-text formats, es->indent
- * corresponds to the nesting depth of logical output groups, and therefore
- * is controlled by ExplainOpenGroup/ExplainCloseGroup.
+ * want it to change at plan-node boundaries (but a few subroutines will
+ * transiently increment it). In non-text formats, es->indent corresponds
+ * to the nesting depth of logical output groups, and therefore is controlled
+ * by ExplainOpenGroup/ExplainCloseGroup.
*/
static void
ExplainNode(PlanState *planstate, List *ancestors,
@@ -1090,9 +1089,20 @@ ExplainNode(PlanState *planstate, List *ancestors,
const char *partialmode = NULL;
const char *operation = NULL;
const char *custom_name = NULL;
+ ExplainWorkersState *save_workers_state = es->workers_state;
int save_indent = es->indent;
bool haschildren;
+ /*
+ * Prepare per-worker output buffers, if needed. We'll append the data in
+ * these to the main output string further down.
+ */
+ if (planstate->worker_instrument && es->analyze && !es->hide_workers)
+ es->workers_state = ExplainCreateWorkersState(planstate->worker_instrument->num_workers);
+ else
+ es->workers_state = NULL;
+
+ /* Identify plan node type, and print generic details */
switch (nodeTag(plan))
{
case T_Result:
@@ -1324,13 +1334,13 @@ ExplainNode(PlanState *planstate, List *ancestors,
{
if (plan_name)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str, "%s\n", plan_name);
es->indent++;
}
if (es->indent)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfoString(es->str, "-> ");
es->indent += 2;
}
@@ -1574,6 +1584,56 @@ ExplainNode(PlanState *planstate, List *ancestors,
if (es->format == EXPLAIN_FORMAT_TEXT)
appendStringInfoChar(es->str, '\n');
+ /* prepare per-worker general execution details */
+ if (es->workers_state && es->verbose)
+ {
+ WorkerInstrumentation *w = planstate->worker_instrument;
+
+ for (int 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(n, es);
+
+ if (es->format == EXPLAIN_FORMAT_TEXT)
+ {
+ ExplainIndentText(es);
+ 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);
+ }
+ 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(n, es);
+ }
+ }
+
/* target list */
if (es->verbose)
show_plan_tlist(planstate, ancestors, es);
@@ -1684,24 +1744,6 @@ ExplainNode(PlanState *planstate, List *ancestors,
nworkers, es);
}
- /*
- * Print per-worker Jit instrumentation. Use same conditions
- * as for the leader's JIT instrumentation, see comment there.
- */
- if (es->costs && es->verbose &&
- outerPlanState(planstate)->worker_jit_instrument)
- {
- PlanState *child = outerPlanState(planstate);
- int n;
- SharedJitInstrumentation *w = child->worker_jit_instrument;
-
- for (n = 0; n < w->num_workers; ++n)
- {
- ExplainPrintJIT(es, child->state->es_jit_flags,
- &w->jit_instr[n], n);
- }
- }
-
if (gather->single_copy || es->format != EXPLAIN_FORMAT_TEXT)
ExplainPropertyBool("Single Copy", gather->single_copy, es);
}
@@ -1881,80 +1923,54 @@ ExplainNode(PlanState *planstate, List *ancestors,
break;
}
+ /*
+ * Prepare per-worker JIT instrumentation. As with the overall JIT
+ * summary, this is printed only if printing costs is enabled.
+ */
+ if (es->workers_state && es->costs && es->verbose)
+ {
+ SharedJitInstrumentation *w = planstate->worker_jit_instrument;
+
+ if (w)
+ {
+ for (int n = 0; n < w->num_workers; n++)
+ {
+ ExplainOpenWorker(n, es);
+ ExplainPrintJIT(es, planstate->state->es_jit_flags,
+ &w->jit_instr[n]);
+ ExplainCloseWorker(n, es);
+ }
+ }
+ }
+
/* Show buffer usage */
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 per-worker buffer usage */
+ if (es->workers_state && es->buffers && es->verbose)
{
WorkerInstrumentation *w = planstate->worker_instrument;
- bool opened_group = false;
- int n;
- for (n = 0; n < w->num_workers; ++n)
+ for (int 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(n, es);
+ show_buffer_usage(es, &instrument->bufusage);
+ ExplainCloseWorker(n, es);
}
-
- if (opened_group)
- ExplainCloseGroup("Workers", "Workers", false, es);
}
+ /* Show per-worker details for this plan node, then pop that stack */
+ if (es->workers_state)
+ ExplainFlushWorkersState(es);
+ es->workers_state = save_workers_state;
+
/* Get ready to display the child plans */
haschildren = planstate->initPlan ||
outerPlanState(planstate) ||
@@ -2525,7 +2541,7 @@ show_tablesample(TableSampleClause *tsc, PlanState *planstate,
{
bool first = true;
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str, "Sampling: %s (", method_name);
foreach(lc, params)
{
@@ -2572,7 +2588,7 @@ show_sort_info(SortState *sortstate, ExplainState *es)
if (es->format == EXPLAIN_FORMAT_TEXT)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str, "Sort Method: %s %s: %ldkB\n",
sortMethod, spaceType, spaceUsed);
}
@@ -2588,12 +2604,14 @@ show_sort_info(SortState *sortstate, ExplainState *es)
* You might think we should just skip this stanza entirely when
* es->hide_workers is true, but then we'd get no sort-method output at
* all. We have to make it look like worker 0's data is top-level data.
- * Currently, we only bother with that for text-format output.
+ * This is easily done by just skipping the OpenWorker/CloseWorker calls.
+ * Currently, we don't worry about the possibility that there are multiple
+ * workers in such a case; if there are, duplicate output fields will be
+ * emitted.
*/
if (sortstate->shared_info != NULL)
{
int n;
- bool opened_group = false;
for (n = 0; n < sortstate->shared_info->num_workers; n++)
{
@@ -2609,32 +2627,26 @@ show_sort_info(SortState *sortstate, ExplainState *es)
spaceType = tuplesort_space_type_name(sinstrument->spaceType);
spaceUsed = sinstrument->spaceUsed;
+ if (es->workers_state)
+ ExplainOpenWorker(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);
+ ExplainIndentText(es);
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 (es->workers_state)
+ ExplainCloseWorker(n, es);
}
- if (opened_group)
- ExplainCloseGroup("Workers", "Workers", false, es);
}
}
@@ -2721,7 +2733,7 @@ show_hash_info(HashState *hashstate, ExplainState *es)
else if (hinstrument.nbatch_original != hinstrument.nbatch ||
hinstrument.nbuckets_original != hinstrument.nbuckets)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str,
"Buckets: %d (originally %d) Batches: %d (originally %d) Memory Usage: %ldkB\n",
hinstrument.nbuckets,
@@ -2732,7 +2744,7 @@ show_hash_info(HashState *hashstate, ExplainState *es)
}
else
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str,
"Buckets: %d Batches: %d Memory Usage: %ldkB\n",
hinstrument.nbuckets, hinstrument.nbatch,
@@ -2758,7 +2770,7 @@ show_tidbitmap_info(BitmapHeapScanState *planstate, ExplainState *es)
{
if (planstate->exact_pages > 0 || planstate->lossy_pages > 0)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfoString(es->str, "Heap Blocks:");
if (planstate->exact_pages > 0)
appendStringInfo(es->str, " exact=%ld", planstate->exact_pages);
@@ -2894,7 +2906,7 @@ show_buffer_usage(ExplainState *es, const BufferUsage *usage)
/* Show only positive counter values. */
if (has_shared || has_local || has_temp)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfoString(es->str, "Buffers:");
if (has_shared)
@@ -2949,7 +2961,7 @@ show_buffer_usage(ExplainState *es, const BufferUsage *usage)
/* As above, show only positive counter values. */
if (has_timing)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfoString(es->str, "I/O Timings:");
if (!INSTR_TIME_IS_ZERO(usage->blk_read_time))
appendStringInfo(es->str, " read=%0.3f",
@@ -3237,7 +3249,7 @@ show_modifytable_info(ModifyTableState *mtstate, List *ancestors,
*/
if (es->format == EXPLAIN_FORMAT_TEXT)
{
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfoString(es->str,
fdwroutine ? foperation : operation);
}
@@ -3427,6 +3439,158 @@ ExplainCustomChildren(CustomScanState *css, List *ancestors, ExplainState *es)
}
/*
+ * Create a per-plan-node workspace for collecting per-worker data.
+ *
+ * Output related to each worker will be temporarily "set aside" into a
+ * separate buffer, which we'll merge into the main output stream once
+ * we've processed all data for the plan node. This makes it feasible to
+ * generate a coherent sub-group of fields for each worker, even though the
+ * code that produces the fields is in several different places in this file.
+ * Formatting of such a set-aside field group is managed by
+ * ExplainOpenSetAsideGroup and ExplainSaveGroup/ExplainRestoreGroup.
+ */
+static ExplainWorkersState *
+ExplainCreateWorkersState(int num_workers)
+{
+ ExplainWorkersState *wstate;
+
+ wstate = (ExplainWorkersState *) palloc(sizeof(ExplainWorkersState));
+ wstate->num_workers = num_workers;
+ wstate->worker_inited = (bool *) palloc0(num_workers * sizeof(bool));
+ wstate->worker_str = (StringInfoData *)
+ palloc0(num_workers * sizeof(StringInfoData));
+ wstate->worker_state_save = (int *) palloc(num_workers * sizeof(int));
+ return wstate;
+}
+
+/*
+ * Begin or resume output into the set-aside group for worker N.
+ */
+static void
+ExplainOpenWorker(int n, ExplainState *es)
+{
+ ExplainWorkersState *wstate = es->workers_state;
+
+ Assert(wstate);
+ Assert(n >= 0 && n < wstate->num_workers);
+
+ /* Save prior output buffer pointer */
+ wstate->prev_str = es->str;
+
+ if (!wstate->worker_inited[n])
+ {
+ /* First time through, so create the buffer for this worker */
+ initStringInfo(&wstate->worker_str[n]);
+ es->str = &wstate->worker_str[n];
+
+ /*
+ * Push suitable initial formatting state for this worker's field
+ * group. We allow one extra logical nesting level, since this group
+ * will eventually be wrapped in an outer "Workers" group.
+ */
+ ExplainOpenSetAsideGroup("Worker", NULL, true, 2, es);
+
+ /*
+ * In non-TEXT formats we always emit a "Worker Number" field, even if
+ * there's no other data for this worker.
+ */
+ if (es->format != EXPLAIN_FORMAT_TEXT)
+ ExplainPropertyInteger("Worker Number", NULL, n, es);
+
+ wstate->worker_inited[n] = true;
+ }
+ else
+ {
+ /* Resuming output for a worker we've already emitted some data for */
+ es->str = &wstate->worker_str[n];
+
+ /* Restore formatting state saved by last ExplainCloseWorker() */
+ ExplainRestoreGroup(es, 2, &wstate->worker_state_save[n]);
+ }
+
+ /*
+ * In TEXT format, prefix the first output line for this worker with
+ * "Worker N:". Then, any additional lines should be indented one more
+ * stop than the "Worker N" line is.
+ */
+ if (es->format == EXPLAIN_FORMAT_TEXT)
+ {
+ if (es->str->len == 0)
+ {
+ ExplainIndentText(es);
+ appendStringInfo(es->str, "Worker %d: ", n);
+ }
+
+ es->indent++;
+ }
+}
+
+/*
+ * End output for worker N --- must pair with previous ExplainOpenWorker call
+ */
+static void
+ExplainCloseWorker(int n, ExplainState *es)
+{
+ ExplainWorkersState *wstate = es->workers_state;
+
+ Assert(wstate);
+ Assert(n >= 0 && n < wstate->num_workers);
+ Assert(wstate->worker_inited[n]);
+
+ /*
+ * Save formatting state in case we do another ExplainOpenWorker(), then
+ * pop the formatting stack.
+ */
+ ExplainSaveGroup(es, 2, &wstate->worker_state_save[n]);
+
+ /*
+ * In TEXT format, if we didn't actually produce any output line(s) then
+ * truncate off the partial line emitted by ExplainOpenWorker. (This is
+ * to avoid bogus output if, say, show_buffer_usage chooses not to print
+ * anything for the worker.) Also fix up the indent level.
+ */
+ if (es->format == EXPLAIN_FORMAT_TEXT)
+ {
+ while (es->str->len > 0 && es->str->data[es->str->len - 1] != '\n')
+ es->str->data[--(es->str->len)] = '\0';
+
+ es->indent--;
+ }
+
+ /* Restore prior output buffer pointer */
+ es->str = wstate->prev_str;
+}
+
+/*
+ * Print per-worker info for current node, then free the ExplainWorkersState.
+ */
+static void
+ExplainFlushWorkersState(ExplainState *es)
+{
+ ExplainWorkersState *wstate = es->workers_state;
+
+ ExplainOpenGroup("Workers", "Workers", false, es);
+ for (int i = 0; i < wstate->num_workers; i++)
+ {
+ if (wstate->worker_inited[i])
+ {
+ /* This must match previous ExplainOpenSetAsideGroup call */
+ ExplainOpenGroup("Worker", NULL, true, es);
+ appendStringInfoString(es->str, wstate->worker_str[i].data);
+ ExplainCloseGroup("Worker", NULL, true, es);
+
+ pfree(wstate->worker_str[i].data);
+ }
+ }
+ ExplainCloseGroup("Workers", "Workers", false, es);
+
+ pfree(wstate->worker_inited);
+ pfree(wstate->worker_str);
+ pfree(wstate->worker_state_save);
+ pfree(wstate);
+}
+
+/*
* Explain a property, such as sort keys or targets, that takes the form of
* a list of unlabeled items. "data" is a list of C strings.
*/
@@ -3439,7 +3603,7 @@ ExplainPropertyList(const char *qlabel, List *data, ExplainState *es)
switch (es->format)
{
case EXPLAIN_FORMAT_TEXT:
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
appendStringInfo(es->str, "%s: ", qlabel);
foreach(lc, data)
{
@@ -3560,7 +3724,7 @@ ExplainProperty(const char *qlabel, const char *unit, const char *value,
switch (es->format)
{
case EXPLAIN_FORMAT_TEXT:
- appendStringInfoSpaces(es->str, es->indent * 2);
+ ExplainIndentText(es);
if (unit)
appendStringInfo(es->str, "%s: %s %s\n", qlabel, value, unit);
else
@@ -3752,6 +3916,117 @@ ExplainCloseGroup(const char *objtype, const char *labelname,
}
/*
+ * Open a group of related objects, without emitting actual data.
+ *
+ * Prepare the formatting state as though we were beginning a group with
+ * the identified properties, but don't actually emit anything. Output
+ * subsequent to this call can be redirected into a separate output buffer,
+ * and then eventually appended to the main output buffer after doing a
+ * regular ExplainOpenGroup call (with the same parameters).
+ *
+ * The extra "depth" parameter is the new group's depth compared to current.
+ * It could be more than one, in case the eventual output will be enclosed
+ * in additional nesting group levels. We assume we don't need to track
+ * formatting state for those levels while preparing this group's output.
+ *
+ * There is no ExplainCloseSetAsideGroup --- in current usage, we always
+ * pop this state with ExplainSaveGroup.
+ */
+static void
+ExplainOpenSetAsideGroup(const char *objtype, const char *labelname,
+ bool labeled, int depth, ExplainState *es)
+{
+ switch (es->format)
+ {
+ case EXPLAIN_FORMAT_TEXT:
+ /* nothing to do */
+ break;
+
+ case EXPLAIN_FORMAT_XML:
+ es->indent += depth;
+ break;
+
+ case EXPLAIN_FORMAT_JSON:
+ es->grouping_stack = lcons_int(0, es->grouping_stack);
+ es->indent += depth;
+ break;
+
+ case EXPLAIN_FORMAT_YAML:
+ if (labelname)
+ es->grouping_stack = lcons_int(1, es->grouping_stack);
+ else
+ es->grouping_stack = lcons_int(0, es->grouping_stack);
+ es->indent += depth;
+ break;
+ }
+}
+
+/*
+ * Pop one level of grouping state, allowing for a re-push later.
+ *
+ * This is typically used after ExplainOpenSetAsideGroup; pass the
+ * same "depth" used for that.
+ *
+ * This should not emit any output. If state needs to be saved,
+ * save it at *state_save. Currently, an integer save area is sufficient
+ * for all formats, but we might need to revisit that someday.
+ */
+static void
+ExplainSaveGroup(ExplainState *es, int depth, int *state_save)
+{
+ switch (es->format)
+ {
+ case EXPLAIN_FORMAT_TEXT:
+ /* nothing to do */
+ break;
+
+ case EXPLAIN_FORMAT_XML:
+ es->indent -= depth;
+ break;
+
+ case EXPLAIN_FORMAT_JSON:
+ es->indent -= depth;
+ *state_save = linitial_int(es->grouping_stack);
+ es->grouping_stack = list_delete_first(es->grouping_stack);
+ break;
+
+ case EXPLAIN_FORMAT_YAML:
+ es->indent -= depth;
+ *state_save = linitial_int(es->grouping_stack);
+ es->grouping_stack = list_delete_first(es->grouping_stack);
+ break;
+ }
+}
+
+/*
+ * Re-push one level of grouping state, undoing the effects of ExplainSaveGroup.
+ */
+static void
+ExplainRestoreGroup(ExplainState *es, int depth, int *state_save)
+{
+ switch (es->format)
+ {
+ case EXPLAIN_FORMAT_TEXT:
+ /* nothing to do */
+ break;
+
+ case EXPLAIN_FORMAT_XML:
+ es->indent += depth;
+ break;
+
+ case EXPLAIN_FORMAT_JSON:
+ es->grouping_stack = lcons_int(*state_save, es->grouping_stack);
+ es->indent += depth;
+ break;
+
+ case EXPLAIN_FORMAT_YAML:
+ es->grouping_stack = lcons_int(*state_save, es->grouping_stack);
+ es->indent += depth;
+ break;
+ }
+}
+
+/*
* Emit a "dummy" group that never has any members.
*
* objtype is the type of the group object, labelname is its label within
@@ -3913,6 +4188,21 @@ ExplainXMLTag(const char *tagname, int flags, ExplainState *es)
}
/*
+ * Indent a text-format line.
+ *
+ * We indent by two spaces per indentation level. However, when emitting
+ * data for a parallel worker there might already be data on the current line
+ * (cf. ExplainOpenWorker); in that case, don't indent any more.
+ */
+static void
+ExplainIndentText(ExplainState *es)
+{
+ Assert(es->format == EXPLAIN_FORMAT_TEXT);
+ if (es->str->len == 0 || es->str->data[es->str->len - 1] == '\n')
+ appendStringInfoSpaces(es->str, es->indent * 2);
+}
+
+/*
* Emit a JSON line ending.
*
* JSON requires a comma after each property but the last. To facilitate this,
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-05 17:07:08 +0000