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add plan text to query one #28

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add plan text to query one #28

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37 changes: 25 additions & 12 deletions pg_stat_sql_plans.c
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Original file line number Diff line number Diff line change
Expand Up @@ -1439,6 +1439,7 @@ pgssp_store(const char *query, uint64 queryId,
}
else
{

/* this part comes from auto_explain
* ExplainPrintPlan has been replaced by
* ExplainOnePlan to be able to be calculated
Expand Down Expand Up @@ -1508,14 +1509,36 @@ pgssp_store(const char *query, uint64 queryId,
{
Size query_offset;
int gc_count;
bool stored;
bool stored = false;
bool do_gc;

if (planId != UINT64CONST(0) && planId != UINT64CONST(1) && planId != UINT64CONST(-1) && pgssp_explain)
{
/* add plan to query text */
char *query_with_plan;
query_with_plan = malloc(query_len + es->str->len + 1 + 1);
strcpy(query_with_plan, query);
strcat(query_with_plan, "\n");
strcat(query_with_plan, es->str->data);
query=query_with_plan;
query_len=strlen(query_with_plan);
// free(query_with_plan);
}

/* Append new query text to file with only shared lock held */
stored = qtext_store( query, query_len,
&query_offset, &gc_count);

//PLY this generates many duplicated query texts in external file (on MSYS2)
// when tested with pgbench -c50 -t5 (a kind of query storm ...)
// In an ideal world:
// - there should be no action between first hash_search and exclusive lock promotion,
// - qtext_store should be executed AFTER hashtable entry creation,
// outside exclusive lock
// query length and offset updated at the same time than counters
// In real life, keep it as is or remove it there (to run it under exclusive lock)
// that may fix initial issue, but reduce performances in the case of many distinct queries.

/*
* Determine whether we need to garbage collect external query texts
* while the shared lock is still held. This micro-optimization
Expand Down Expand Up @@ -1548,17 +1571,7 @@ pgssp_store(const char *query, uint64 queryId,
/* If needed, perform garbage collection while exclusive lock held */
if (do_gc)
gc_qtexts();

if (planId != UINT64CONST(0) && planId != UINT64CONST(1) && planId != UINT64CONST(-1) && pgssp_explain)
{
/*
* Plan is only logged one time for each queryid / planId
*/
ereport(LOG,
(errmsg("qpid: %lld queryid: %lld planid: %lld plan:\n%s",
(long long)qpId, (long long)queryId, (long long)planId, es->str->data),
errhidecontext(true), errhidestmt(true)));
}

}


Expand Down