#include "pgpa_output.h"
#include "pgpa_walker.h"
+#include "commands/defrem.h"
+#include "commands/explain.h"
+#include "commands/explain_format.h"
+#include "commands/explain_state.h"
#include "funcapi.h"
#include "storage/dsm_registry.h"
#include "utils/guc.h"
PG_MODULE_MAGIC;
-static pgpa_shared_state *pgpa_state = NULL;
+static pgpa_shared_state * pgpa_state = NULL;
static dsa_area *pgpa_dsa_area = NULL;
/* GUC variables */
-int pg_plan_advice_local_collection_limit = 0;
-int pg_plan_advice_shared_collection_limit = 0;
+int pg_plan_advice_local_collection_limit = 0;
+int pg_plan_advice_shared_collection_limit = 0;
/* Saved hook values */
static ExecutorStart_hook_type prev_ExecutorStart = NULL;
+static explain_per_plan_hook_type prev_explain_per_plan_hook = NULL;
-/* Memory context */
+/* Other file-level globals */
+static int es_extension_id;
static MemoryContext pgpa_memory_context = NULL;
static bool pg_plan_advice_ExecutorStart(QueryDesc *queryDesc, int eflags);
-static void pgpa_generate_advice(PlannedStmt *pstmt, const char *query_string);
+static void pg_plan_advice_explain_option_handler(ExplainState *es,
+ DefElem *opt,
+ ParseState *pstate);
+static void pg_plan_advice_explain_per_plan_hook(PlannedStmt *plannedstmt,
+ IntoClause *into,
+ ExplainState *es,
+ const char *queryString,
+ ParamListInfo params,
+ QueryEnvironment *queryEnv);
+static char *pg_plan_advice_generate(PlannedStmt *pstmt);
/*
* Initialize this module.
NULL,
NULL);
+ /* Get an ID that we can use to cache data in an ExplainState. */
+ es_extension_id = GetExplainExtensionId("pg_plan_advice");
+
+ /* Register the new EXPLAIN options implemented by this module. */
+ RegisterExtensionExplainOption("plan_advice",
+ pg_plan_advice_explain_option_handler);
+
/* Install hooks */
prev_ExecutorStart = ExecutorStart_hook;
ExecutorStart_hook = pg_plan_advice_ExecutorStart;
+ prev_explain_per_plan_hook = explain_per_plan_hook;
+ explain_per_plan_hook = pg_plan_advice_explain_per_plan_hook;
}
/*
{
pgpa_shared_state *state = pg_plan_advice_attach();
dsa_handle area_handle;
- MemoryContext oldcontext;
+ MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(pg_plan_advice_get_mcxt());
if (pg_plan_advice_local_collection_limit > 0
|| pg_plan_advice_shared_collection_limit > 0)
- pgpa_generate_advice(pstmt, queryDesc->sourceText);
+ {
+ char *advice;
+
+ advice = pg_plan_advice_generate(pstmt);
+
+ /*
+ * If the advice string is non-empty, pass it to the collectors.
+ *
+ * A query such as SELECT 2+2 or SELECT * FROM generate_series(1,10)
+ * will not produce any advice, since there are no query planning
+ * decisions that can be influenced. It wouldn't exactly be wrong to
+ * record the query together with the empty advice string, but there
+ * doesn't seem to be much value in it, so skip it to save space.
+ *
+ * If this proves confusing to users, we might need to revist the
+ * behavior here.
+ */
+ if (advice[0] != '\0')
+ pgpa_collect_advice(pstmt->queryId, queryDesc->sourceText,
+ advice);
+ }
if (prev_ExecutorStart)
return prev_ExecutorStart(queryDesc, eflags);
}
/*
- * Generate advice from a query plan and send it to the relevant collectors.
+ * Handler for EXPLAIN (PLAN_ADVICE).
*/
static void
-pgpa_generate_advice(PlannedStmt *pstmt, const char *query_string)
+pg_plan_advice_explain_option_handler(ExplainState *es, DefElem *opt,
+ ParseState *pstate)
+{
+ bool *plan_advice;
+
+ plan_advice = GetExplainExtensionState(es, es_extension_id);
+
+ if (plan_advice == NULL)
+ {
+ plan_advice = palloc0_object(bool);
+ SetExplainExtensionState(es, es_extension_id, plan_advice);
+ }
+
+ *plan_advice = defGetBoolean(opt);
+}
+
+/*
+ * If the PLAN_ADVICE option was specified -- and not set to FALSE -- generate
+ * advice from the provided plan and add it to the EXPLAIN output.
+ */
+static void
+pg_plan_advice_explain_per_plan_hook(PlannedStmt *plannedstmt,
+ IntoClause *into,
+ ExplainState *es,
+ const char *queryString,
+ ParamListInfo params,
+ QueryEnvironment *queryEnv)
+{
+ bool *plan_advice;
+
+ if (prev_explain_per_plan_hook)
+ prev_explain_per_plan_hook(plannedstmt, into, es, queryString,
+ params, queryEnv);
+
+ plan_advice = GetExplainExtensionState(es, es_extension_id);
+ if (plan_advice != NULL && *plan_advice)
+ {
+ char *advice = pg_plan_advice_generate(plannedstmt);
+
+ /*
+ * The advice string likely spans multiple lines; the last line will
+ * not end in a newline, but the others will. In text format, it looks
+ * nicest to indent each line of the advice separately, beginning on
+ * the line below the "Plan Advice" label. For non-text formats, it's
+ * best not to add any special handling.
+ */
+ if (es->format != EXPLAIN_FORMAT_TEXT)
+ ExplainPropertyText("Plan Advice", advice, es);
+ else if (*advice != '\0')
+ {
+ char *s;
+
+ ExplainIndentText(es);
+ appendStringInfo(es->str, "Plan Advice:\n");
+
+ es->indent++;
+
+ while ((s = strchr(advice, '\n')) != NULL)
+ {
+ ExplainIndentText(es);
+ appendBinaryStringInfo(es->str, advice, (s - advice) + 1);
+ advice = s + 1;
+ }
+
+ if (*advice != '\0')
+ {
+ ExplainIndentText(es);
+ appendStringInfo(es->str, "%s\n", advice);
+ }
+
+ es->indent--;
+ }
+ }
+}
+
+/*
+ * Generate advice from a query plan and send it to the relevant collectors.
+ */
+static char *
+pg_plan_advice_generate(PlannedStmt *pstmt)
{
pgpa_plan_walker_context context;
StringInfoData buf;
/* Put advice into string form. */
initStringInfo(&buf);
pgpa_output_advice(&buf, &context, rt_identifiers);
-
- /*
- * If the advice string is non-empty, pass it to the collectors.
- *
- * A query such as SELECT 2+2 or SELECT * FROM generate_series(1,10)
- * will not produce any advice, since there are no query planning decisions
- * that can be influenced. It wouldn't exactly be wrong to record the
- * query together with the empty advice string, but there doesn't seem to
- * be much value in it, so skip it to save space.
- *
- * If this proves confusing to users, we might need to revist the behavior
- * here.
- */
- if (buf.data[0] != '\0')
- pgpa_collect_advice(pstmt->queryId, query_string, buf.data);
+ return buf.data;
}
projects / users / rhaas / postgres.git / commitdiff