Transform proconfig for faster execution.

Store function config settings in lists to avoid the need to parse and
allocate for each function execution.

Speedup is modest but significant. Additionally, this change also
seems cleaner and supports some other performance improvements under
discussion.

Discussion: https://postgr.es/m/04c8592dbd694e4114a3ed87139a7a04e4363030[email protected]
Reviewed-by: Nathan Bossart

diff --git a/src/backend/utils/fmgr/fmgr.c b/src/backend/utils/fmgr/fmgr.c
index 9208c31fe06ad7ee5e1cadfa7eceec32a4f965cf..6b2d7d7be38161c32f77e6bfd6b4ff5468f7d078 100644 (file)
--- a/src/backend/utils/fmgr/fmgr.c
+++ b/src/backend/utils/fmgr/fmgr.c
@@ -612,7 +612,8 @@ struct fmgr_security_definer_cache
 {
    FmgrInfo    flinfo;         /* lookup info for target function */
    Oid         userid;         /* userid to set, or InvalidOid */
-   ArrayType  *proconfig;      /* GUC values to set, or NULL */
+   List       *configNames;    /* GUC names to set, or NIL */
+   List       *configValues;   /* GUC values to set, or NIL */
    Datum       arg;            /* passthrough argument for plugin modules */
 };
 
@@ -634,6 +635,8 @@ fmgr_security_definer(PG_FUNCTION_ARGS)
    FmgrInfo   *save_flinfo;
    Oid         save_userid;
    int         save_sec_context;
+   ListCell   *lc1;
+   ListCell   *lc2;
    volatile int save_nestlevel;
    PgStat_FunctionCallUsage fcusage;
 
@@ -666,8 +669,11 @@ fmgr_security_definer(PG_FUNCTION_ARGS)
                                &isnull);
        if (!isnull)
        {
+           ArrayType *array;
            oldcxt = MemoryContextSwitchTo(fcinfo->flinfo->fn_mcxt);
-           fcache->proconfig = DatumGetArrayTypePCopy(datum);
+           array = DatumGetArrayTypeP(datum);
+           TransformGUCArray(array, &fcache->configNames,
+                             &fcache->configValues);
            MemoryContextSwitchTo(oldcxt);
        }
 
@@ -680,7 +686,7 @@ fmgr_security_definer(PG_FUNCTION_ARGS)
 
    /* GetUserIdAndSecContext is cheap enough that no harm in a wasted call */
    GetUserIdAndSecContext(&save_userid, &save_sec_context);
-   if (fcache->proconfig)      /* Need a new GUC nesting level */
+   if (fcache->configNames != NIL)     /* Need a new GUC nesting level */
        save_nestlevel = NewGUCNestLevel();
    else
        save_nestlevel = 0;     /* keep compiler quiet */
@@ -689,12 +695,17 @@ fmgr_security_definer(PG_FUNCTION_ARGS)
        SetUserIdAndSecContext(fcache->userid,
                               save_sec_context | SECURITY_LOCAL_USERID_CHANGE);
 
-   if (fcache->proconfig)
+   forboth(lc1, fcache->configNames, lc2, fcache->configValues)
    {
-       ProcessGUCArray(fcache->proconfig,
-                       (superuser() ? PGC_SUSET : PGC_USERSET),
-                       PGC_S_SESSION,
-                       GUC_ACTION_SAVE);
+       GucContext   context = superuser() ? PGC_SUSET : PGC_USERSET;
+       GucSource    source  = PGC_S_SESSION;
+       GucAction    action  = GUC_ACTION_SAVE;
+       char        *name    = lfirst(lc1);
+       char        *value   = lfirst(lc2);
+
+       (void) set_config_option(name, value,
+                                context, source,
+                                action, true, 0, false);
    }
 
    /* function manager hook */
@@ -737,7 +748,7 @@ fmgr_security_definer(PG_FUNCTION_ARGS)
 
    fcinfo->flinfo = save_flinfo;
 
-   if (fcache->proconfig)
+   if (fcache->configNames != NIL)
        AtEOXact_GUC(true, save_nestlevel);
    if (OidIsValid(fcache->userid))
        SetUserIdAndSecContext(save_userid, save_sec_context);

diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 5308896c87fbd7b92c4ae9f53fc343b3ff093469..3449470953a14c75a046ef5b3e1a18fd29d0fd5a 100644 (file)
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -6215,14 +6215,12 @@ ParseLongOption(const char *string, char **name, char **value)
 
 
 /*
- * Handle options fetched from pg_db_role_setting.setconfig,
- * pg_proc.proconfig, etc.  Caller must specify proper context/source/action.
- *
- * The array parameter must be an array of TEXT (it must not be NULL).
+ * Transform array of GUC settings into lists of names and values. The lists
+ * are faster to process in cases where the settings must be applied
+ * repeatedly (e.g. for each function invocation).
  */
 void
-ProcessGUCArray(ArrayType *array,
-               GucContext context, GucSource source, GucAction action)
+TransformGUCArray(ArrayType *array, List **names, List **values)
 {
    int         i;
 
@@ -6231,6 +6229,8 @@ ProcessGUCArray(ArrayType *array,
    Assert(ARR_NDIM(array) == 1);
    Assert(ARR_LBOUND(array)[0] == 1);
 
+   *names = NIL;
+   *values = NIL;
    for (i = 1; i <= ARR_DIMS(array)[0]; i++)
    {
        Datum       d;
@@ -6262,14 +6262,45 @@ ProcessGUCArray(ArrayType *array,
            continue;
        }
 
+       *names = lappend(*names, name);
+       *values = lappend(*values, value);
+
+       pfree(s);
+   }
+}
+
+
+/*
+ * Handle options fetched from pg_db_role_setting.setconfig,
+ * pg_proc.proconfig, etc.  Caller must specify proper context/source/action.
+ *
+ * The array parameter must be an array of TEXT (it must not be NULL).
+ */
+void
+ProcessGUCArray(ArrayType *array,
+               GucContext context, GucSource source, GucAction action)
+{
+   List *gucNames;
+   List *gucValues;
+   ListCell *lc1;
+   ListCell *lc2;
+
+   TransformGUCArray(array, &gucNames, &gucValues);
+   forboth(lc1, gucNames, lc2, gucValues)
+   {
+       char *name = lfirst(lc1);
+       char *value = lfirst(lc2);
+
        (void) set_config_option(name, value,
                                 context, source,
                                 action, true, 0, false);
 
        pfree(name);
        pfree(value);
-       pfree(s);
    }
+
+   list_free(gucNames);
+   list_free(gucValues);
 }
 
 

diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index 223a19f80d87b8d0f5c7fc526c7a506a0f87ae33..e89083ee0e6e30fb8dfd04b11cd4d9a7f258e49d 100644 (file)
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -391,6 +391,8 @@ extern void AlterSystemSetConfigFile(AlterSystemStmt *altersysstmt);
 extern char *GetConfigOptionByName(const char *name, const char **varname,
                                   bool missing_ok);
 
+extern void TransformGUCArray(ArrayType *array, List **configNames,
+                             List **configValues);
 extern void ProcessGUCArray(ArrayType *array,
                            GucContext context, GucSource source, GucAction action);
 extern ArrayType *GUCArrayAdd(ArrayType *array, const char *name, const char *value);