database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-11-24 00:23:06 +03:00
Code Activity

Represent command completion tags as structs

Browse Source 
The backend was using strings to represent command tags and doing string
comparisons in multiple places, but that's slow and unhelpful.  Create a
new command list with a supporting structure to use instead; this is
stored in a tag-list-file that can be tailored to specific purposes with
a caller-definable C macro, similar to what we do for WAL resource
managers.  The first first such uses are a new CommandTag enum and a
CommandTagBehavior struct.

Replace numerous occurrences of char *completionTag with a
QueryCompletion struct so that the code no longer stores information
about completed queries in a cstring.  Only at the last moment, in
EndCommand(), does this get converted to a string.

EventTriggerCacheItem no longer holds an array of palloc’d tag strings
in sorted order, but rather just a Bitmapset over the CommandTags.

Author: Mark Dilger, with unsolicited help from Álvaro Herrera
Reviewed-by: John Naylor, Tom Lane
Discussion: https://postgr.es/m/981A9DB4-3F0C-4DA5-88AD-CB9CFF4D6CAD@enterprisedb.com
This commit is contained in:
Alvaro Herrera
2020-03-02 18:19:51 -03:00
parent 7b425a5283
commit 2f9661311b
39 changed files with 877 additions and 621 deletions
Download Patch File Download Diff File Expand all files Collapse all files

112
src/backend/tcop/pquery.c
View File

@@ -40,7 +40,7 @@ static void ProcessQuery(PlannedStmt *plan,
ParamListInfo params,
QueryEnvironment *queryEnv,
DestReceiver *dest,
char *completionTag);
QueryCompletion *qc);
static void FillPortalStore(Portal portal, bool isTopLevel);
static uint64 RunFromStore(Portal portal, ScanDirection direction, uint64 count,
DestReceiver *dest);
@@ -48,11 +48,11 @@ static uint64 PortalRunSelect(Portal portal, bool forward, long count,
DestReceiver *dest);
static void PortalRunUtility(Portal portal, PlannedStmt *pstmt,
bool isTopLevel, bool setHoldSnapshot,
DestReceiver *dest, char *completionTag);
DestReceiver *dest, QueryCompletion *qc);
static void PortalRunMulti(Portal portal,
bool isTopLevel, bool setHoldSnapshot,
DestReceiver *dest, DestReceiver *altdest,
char *completionTag);
QueryCompletion *qc);
static uint64 DoPortalRunFetch(Portal portal,
FetchDirection fdirection,
long count,
@@ -125,10 +125,9 @@ FreeQueryDesc(QueryDesc *qdesc)
* sourceText: the source text of the query
* params: any parameters needed
* dest: where to send results
* completionTag: points to a buffer of size COMPLETION_TAG_BUFSIZE
* in which to store a command completion status string.
* qc: where to store the command completion status data.
*
* completionTag may be NULL if caller doesn't want a status string.
* qc may be NULL if caller doesn't want a status string.
*
* Must be called in a memory context that will be reset or deleted on
* error; otherwise the executor's memory usage will be leaked.
@@ -139,7 +138,7 @@ ProcessQuery(PlannedStmt *plan,
ParamListInfo params,
QueryEnvironment *queryEnv,
DestReceiver *dest,
char *completionTag)
QueryCompletion *qc)
{
QueryDesc *queryDesc;
@@ -161,38 +160,26 @@ ProcessQuery(PlannedStmt *plan,
ExecutorRun(queryDesc, ForwardScanDirection, 0L, true);
/*
* Build command completion status string, if caller wants one.
* Build command completion status data, if caller wants one.
*/
if (completionTag)
if (qc)
{
Oid lastOid;
switch (queryDesc->operation)
{
case CMD_SELECT:
snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
"SELECT " UINT64_FORMAT,
queryDesc->estate->es_processed);
SetQueryCompletion(qc, CMDTAG_SELECT, queryDesc->estate->es_processed);
break;
case CMD_INSERT:
/* lastoid doesn't exist anymore */
lastOid = InvalidOid;
snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
"INSERT %u " UINT64_FORMAT,
lastOid, queryDesc->estate->es_processed);
SetQueryCompletion(qc, CMDTAG_INSERT, queryDesc->estate->es_processed);
break;
case CMD_UPDATE:
snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
"UPDATE " UINT64_FORMAT,
queryDesc->estate->es_processed);
SetQueryCompletion(qc, CMDTAG_UPDATE, queryDesc->estate->es_processed);
break;
case CMD_DELETE:
snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
"DELETE " UINT64_FORMAT,
queryDesc->estate->es_processed);
SetQueryCompletion(qc, CMDTAG_DELETE, queryDesc->estate->es_processed);
break;
default:
strcpy(completionTag, "???");
SetQueryCompletion(qc, CMDTAG_UNKNOWN, queryDesc->estate->es_processed);
break;
}
}
@@ -675,9 +662,8 @@ PortalSetResultFormat(Portal portal, int nFormats, int16 *formats)
*
* altdest: where to send output of non-primary queries
*
* completionTag: points to a buffer of size COMPLETION_TAG_BUFSIZE
* in which to store a command completion status string.
* May be NULL if caller doesn't want a status string.
* qc: where to store command completion status data.
* May be NULL if caller doesn't want status data.
*
* Returns true if the portal's execution is complete, false if it was
* suspended due to exhaustion of the count parameter.
@@ -685,7 +671,7 @@ PortalSetResultFormat(Portal portal, int nFormats, int16 *formats)
bool
PortalRun(Portal portal, long count, bool isTopLevel, bool run_once,
DestReceiver *dest, DestReceiver *altdest,
char *completionTag)
QueryCompletion *qc)
{
bool result;
uint64 nprocessed;
@@ -700,9 +686,9 @@ PortalRun(Portal portal, long count, bool isTopLevel, bool run_once,
TRACE_POSTGRESQL_QUERY_EXECUTE_START();
/* Initialize completion tag to empty string */
if (completionTag)
completionTag[0] = '\0';
/* Initialize empty completion data */
if (qc)
InitializeQueryCompletion(qc);
if (log_executor_stats && portal->strategy != PORTAL_MULTI_QUERY)
{
@@ -771,16 +757,13 @@ PortalRun(Portal portal, long count, bool isTopLevel, bool run_once,
/*
* If the portal result contains a command tag and the caller
* gave us a pointer to store it, copy it. Patch the "SELECT"
* tag to also provide the rowcount.
* gave us a pointer to store it, copy it and update the
* rowcount.
*/
if (completionTag && portal->commandTag)
if (qc && portal->qc.commandTag != CMDTAG_UNKNOWN)
{
if (strcmp(portal->commandTag, "SELECT") == 0)
snprintf(completionTag, COMPLETION_TAG_BUFSIZE,
"SELECT " UINT64_FORMAT, nprocessed);
else
strcpy(completionTag, portal->commandTag);
CopyQueryCompletion(qc, &portal->qc);
qc->nprocessed = nprocessed;
}
/* Mark portal not active */
@@ -794,7 +777,7 @@ PortalRun(Portal portal, long count, bool isTopLevel, bool run_once,
case PORTAL_MULTI_QUERY:
PortalRunMulti(portal, isTopLevel, false,
dest, altdest, completionTag);
dest, altdest, qc);
/* Prevent portal's commands from being re-executed */
MarkPortalDone(portal);
@@ -1005,8 +988,9 @@ static void
FillPortalStore(Portal portal, bool isTopLevel)
{
DestReceiver *treceiver;
char completionTag[COMPLETION_TAG_BUFSIZE];
QueryCompletion qc;
InitializeQueryCompletion(&qc);
PortalCreateHoldStore(portal);
treceiver = CreateDestReceiver(DestTuplestore);
SetTuplestoreDestReceiverParams(treceiver,
@@ -1014,8 +998,6 @@ FillPortalStore(Portal portal, bool isTopLevel)
portal->holdContext,
false);
completionTag[0] = '\0';
switch (portal->strategy)
{
case PORTAL_ONE_RETURNING:
@@ -1028,12 +1010,12 @@ FillPortalStore(Portal portal, bool isTopLevel)
* portal's holdSnapshot to the snapshot used (or a copy of it).
*/
PortalRunMulti(portal, isTopLevel, true,
treceiver, None_Receiver, completionTag);
treceiver, None_Receiver, &qc);
break;
case PORTAL_UTIL_SELECT:
PortalRunUtility(portal, linitial_node(PlannedStmt, portal->stmts),
isTopLevel, true, treceiver, completionTag);
isTopLevel, true, treceiver, &qc);
break;
default:
@@ -1042,9 +1024,9 @@ FillPortalStore(Portal portal, bool isTopLevel)
break;
}
/* Override default completion tag with actual command result */
if (completionTag[0] != '\0')
portal->commandTag = pstrdup(completionTag);
/* Override portal completion data with actual command results */
if (qc.commandTag != CMDTAG_UNKNOWN)
CopyQueryCompletion(&portal->qc, &qc);
treceiver->rDestroy(treceiver);
}
@@ -1130,7 +1112,7 @@ RunFromStore(Portal portal, ScanDirection direction, uint64 count,
static void
PortalRunUtility(Portal portal, PlannedStmt *pstmt,
bool isTopLevel, bool setHoldSnapshot,
DestReceiver *dest, char *completionTag)
DestReceiver *dest, QueryCompletion *qc)
{
Node *utilityStmt = pstmt->utilityStmt;
Snapshot snapshot;
@@ -1178,7 +1160,7 @@ PortalRunUtility(Portal portal, PlannedStmt *pstmt,
portal->portalParams,
portal->queryEnv,
dest,
completionTag);
qc);
/* Some utility statements may change context on us */
MemoryContextSwitchTo(portal->portalContext);
@@ -1202,7 +1184,7 @@ static void
PortalRunMulti(Portal portal,
bool isTopLevel, bool setHoldSnapshot,
DestReceiver *dest, DestReceiver *altdest,
char *completionTag)
QueryCompletion *qc)
{
bool active_snapshot_set = false;
ListCell *stmtlist_item;
@@ -1284,7 +1266,7 @@ PortalRunMulti(Portal portal,
portal->sourceText,
portal->portalParams,
portal->queryEnv,
dest, completionTag);
dest, qc);
}
else
{
@@ -1319,7 +1301,7 @@ PortalRunMulti(Portal portal,
Assert(!active_snapshot_set);
/* statement can set tag string */
PortalRunUtility(portal, pstmt, isTopLevel, false,
dest, completionTag);
dest, qc);
}
else
{
@@ -1350,8 +1332,8 @@ PortalRunMulti(Portal portal,
PopActiveSnapshot();
/*
* If a command completion tag was supplied, use it. Otherwise use the
* portal's commandTag as the default completion tag.
* If a query completion data was supplied, use it. Otherwise use the
* portal's query completion data.
*
* Exception: Clients expect INSERT/UPDATE/DELETE tags to have counts, so
* fake them with zeros. This can happen with DO INSTEAD rules if there
@@ -1361,18 +1343,12 @@ PortalRunMulti(Portal portal,
* e.g. an INSERT that does an UPDATE instead should not print "0 1" if
* one row was updated. See QueryRewrite(), step 3, for details.
*/
if (completionTag && completionTag[0] == '\0')
if (qc && qc->commandTag == CMDTAG_UNKNOWN)
{
if (portal->commandTag)
strcpy(completionTag, portal->commandTag);
if (strcmp(completionTag, "SELECT") == 0)
sprintf(completionTag, "SELECT 0 0");
else if (strcmp(completionTag, "INSERT") == 0)
strcpy(completionTag, "INSERT 0 0");
else if (strcmp(completionTag, "UPDATE") == 0)
strcpy(completionTag, "UPDATE 0");
else if (strcmp(completionTag, "DELETE") == 0)
strcpy(completionTag, "DELETE 0");
if (portal->qc.commandTag != CMDTAG_UNKNOWN)
CopyQueryCompletion(qc, &portal->qc);
/* If the caller supplied a qc, we should have set it by now. */
Assert(qc->commandTag != CMDTAG_UNKNOWN);
}
}