Performance improvement to evergreen.ranked_volumes() database function.

For the client I analyzed logs from production Pg instance for ~ 10
days.

During this time, the single most time consuming query (summarized time
for all instances of the query, with different parameters) was:

SELECT * FROM unapi.bre ( ... ) AS "unapi.bre";

I profiled this function, and found that in my test case most of the
time (2.04s out of 2.06s, so ~ 99%) was spent in call to
unapi.holdings_xml() function.

When I profiled this function, I found that most of the time (sorry,
don't have the number now with me) was spent in call to
evergreen.ranked_volumes() function.

At this moment in my research something changed on the server I was
testing on, and all subsequent times were ~ 4-5 times lower, but the
ratios were more or less the same.

Anyway - call to evergreen.ranked_volumes() showed repeatable time (with
full caches/buffers) of ~ 380ms.

I modified the function by:
1. inlining actor.org_unit_descendants(?, ?)
2. inlining evergreen.rank_ou(?, ?, ?)
3. extracting depth calculation to separate call
4. switched to plpgsql (which gives me ability to use variables)
5. removed evergreen.rank_ou() and evergreen.rank_cp_status() from
   select clause - these are still in WINDOW definition, but they
   weren't used in the SELECT, so it's better to remove from there.
6. in passing renamed arguments to avoid name clash (argument depth vs.
   field depth)
7. in passing changed usage of $* to access parameters to using named
   parameters, for readability.

New function did the same work in ~ 18ms.

diff --git a/Open-ILS/src/sql/Pg/990.schema.unapi.sql b/Open-ILS/src/sql/Pg/990.schema.unapi.sql
index 78a9a2c..2037f9f 100644 (file)
--- a/Open-ILS/src/sql/Pg/990.schema.unapi.sql
+++ b/Open-ILS/src/sql/Pg/990.schema.unapi.sql
@@ -65,32 +65,80 @@ RETURNS INTEGER AS $$
 $$ LANGUAGE SQL STABLE;
 
 CREATE OR REPLACE FUNCTION evergreen.ranked_volumes(
-    bibid BIGINT, 
-    ouid INT,
-    depth INT DEFAULT NULL,
-    slimit HSTORE DEFAULT NULL,
-    soffset HSTORE DEFAULT NULL,
-    pref_lib INT DEFAULT NULL,
-    includes TEXT[] DEFAULT NULL::TEXT[]
-) RETURNS TABLE (id BIGINT, name TEXT, label_sortkey TEXT, rank BIGINT) AS $$
+    p_bibid bigint,
+    p_ouid integer,
+    p_depth integer DEFAULT NULL::integer,
+    p_slimit public.hstore DEFAULT NULL::public.hstore,
+    p_soffset public.hstore DEFAULT NULL::public.hstore,
+    p_pref_lib integer DEFAULT NULL::integer,
+    p_includes text[] DEFAULT NULL::text[]
+) RETURNS TABLE(
+    id bigint,
+    name text,
+    label_sortkey text,
+    rank bigint
+)
+LANGUAGE plpgsql
+STABLE
+AS $_$
+DECLARE
+    v_depth int4;
+BEGIN
+    v_depth := coalesce(
+        p_depth,
+        (
+            SELECT depth
+            FROM actor.org_unit_type aout
+                INNER JOIN actor.org_unit ou ON ou_type = aout.id
+            WHERE ou.id = p_ouid
+        ),
+        p_pref_lib
+    );
+
+    RETURN QUERY
+    WITH RECURSIVE descendant_depth AS (
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+                JOIN anscestor_depth ad ON (ad.id = ou.id)
+        WHERE ad.depth = v_depth
+            UNION ALL
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+                JOIN descendant_depth ot ON (ot.id = ou.parent_ou)
+    ), anscestor_depth AS (
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+        WHERE ou.id = p_ouid
+            UNION ALL
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+                JOIN anscestor_depth ot ON (ot.parent_ou = ou.id)
+    ), descendants as (
+        SELECT ou.* FROM actor.org_unit ou JOIN descendant_depth USING (id)
+    )
+
     SELECT ua.id, ua.name, ua.label_sortkey, MIN(ua.rank) AS rank FROM (
         SELECT acn.id, aou.name, acn.label_sortkey,
-            evergreen.rank_ou(aou.id, $2, $6), evergreen.rank_cp_status(acp.status),
             RANK() OVER w
         FROM asset.call_number acn
             JOIN asset.copy acp ON (acn.id = acp.call_number)
-            JOIN actor.org_unit_descendants( $2, COALESCE(
-                $3, (
-                    SELECT depth
-                    FROM actor.org_unit_type aout
-                        INNER JOIN actor.org_unit ou ON ou_type = aout.id
-                    WHERE ou.id = $2
-                ), $6)
-            ) AS aou ON (acp.circ_lib = aou.id)
-        WHERE acn.record = $1
+            JOIN descendants AS aou ON (acp.circ_lib = aou.id)
+        WHERE acn.record = p_bibid
             AND acn.deleted IS FALSE
             AND acp.deleted IS FALSE
-            AND CASE WHEN ('exclude_invisible_acn' = ANY($7)) THEN 
+            AND CASE WHEN ('exclude_invisible_acn' = ANY(p_includes)) THEN 
                 EXISTS (
                     SELECT 1 
                     FROM asset.opac_visible_copies 
@@ -98,15 +146,26 @@ CREATE OR REPLACE FUNCTION evergreen.ranked_volumes(
                 ) ELSE TRUE END
         GROUP BY acn.id, acp.status, aou.name, acn.label_sortkey, aou.id
         WINDOW w AS (
-            ORDER BY evergreen.rank_ou(aou.id, $2, $6), evergreen.rank_cp_status(acp.status)
+            ORDER BY 
+                COALESCE(
+                    CASE WHEN aou.id = p_ouid THEN -20000 END,
+                    CASE WHEN aou.id = p_pref_lib THEN -10000 END,
+                    (SELECT distance - 5000
+                        FROM actor.org_unit_descendants_distance(p_pref_lib) as x
+                        WHERE x.id = aou.id AND p_pref_lib IN (
+                            SELECT q.id FROM actor.org_unit_descendants(p_ouid) as q)),
+                    (SELECT e.distance FROM actor.org_unit_descendants_distance(p_ouid) as e WHERE e.id = aou.id),
+                    1000
+                ),
+                evergreen.rank_cp_status(acp.status)
         )
     ) AS ua
     GROUP BY ua.id, ua.name, ua.label_sortkey
     ORDER BY rank, ua.name, ua.label_sortkey
-    LIMIT ($4 -> 'acn')::INT
-    OFFSET ($5 -> 'acn')::INT;
-$$
-LANGUAGE SQL STABLE;
+    LIMIT (p_slimit -> 'acn')::INT
+    OFFSET (p_soffset -> 'acn')::INT;
+END;
+$_$;
 
 CREATE OR REPLACE FUNCTION evergreen.located_uris (
     bibid BIGINT, 

diff --git a/Open-ILS/src/sql/Pg/upgrade/XXXX.function.ranked_volumes.sql b/Open-ILS/src/sql/Pg/upgrade/XXXX.function.ranked_volumes.sql
new file mode 100644 (file)
index 0000000..c5e5026
--- /dev/null
+++ b/Open-ILS/src/sql/Pg/upgrade/XXXX.function.ranked_volumes.sql
@@ -0,0 +1,102 @@
+CREATE OR REPLACE FUNCTION evergreen.ranked_volumes(
+    p_bibid bigint,
+    p_ouid integer,
+    p_depth integer DEFAULT NULL::integer,
+    p_slimit public.hstore DEFAULT NULL::public.hstore,
+    p_soffset public.hstore DEFAULT NULL::public.hstore,
+    p_pref_lib integer DEFAULT NULL::integer,
+    p_includes text[] DEFAULT NULL::text[]
+) RETURNS TABLE(
+    id bigint,
+    name text,
+    label_sortkey text,
+    rank bigint
+)
+LANGUAGE plpgsql
+STABLE
+AS $_$
+DECLARE
+    v_depth int4;
+BEGIN
+    v_depth := coalesce(
+        p_depth,
+        (
+            SELECT depth
+            FROM actor.org_unit_type aout
+                INNER JOIN actor.org_unit ou ON ou_type = aout.id
+            WHERE ou.id = p_ouid
+        ),
+        p_pref_lib
+    );
+
+    RETURN QUERY
+    WITH RECURSIVE descendant_depth AS (
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+                JOIN anscestor_depth ad ON (ad.id = ou.id)
+        WHERE ad.depth = v_depth
+            UNION ALL
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+                JOIN descendant_depth ot ON (ot.id = ou.parent_ou)
+    ), anscestor_depth AS (
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+        WHERE ou.id = p_ouid
+            UNION ALL
+        SELECT  ou.id,
+                ou.parent_ou,
+                out.depth
+        FROM  actor.org_unit ou
+                JOIN actor.org_unit_type out ON (out.id = ou.ou_type)
+                JOIN anscestor_depth ot ON (ot.parent_ou = ou.id)
+    ), descendants as (
+        SELECT ou.* FROM actor.org_unit ou JOIN descendant_depth USING (id)
+    )
+
+    SELECT ua.id, ua.name, ua.label_sortkey, MIN(ua.rank) AS rank FROM (
+        SELECT acn.id, aou.name, acn.label_sortkey,
+            RANK() OVER w
+        FROM asset.call_number acn
+            JOIN asset.copy acp ON (acn.id = acp.call_number)
+            JOIN descendants AS aou ON (acp.circ_lib = aou.id)
+        WHERE acn.record = p_bibid
+            AND acn.deleted IS FALSE
+            AND acp.deleted IS FALSE
+            AND CASE WHEN ('exclude_invisible_acn' = ANY(p_includes)) THEN 
+                EXISTS (
+                    SELECT 1 
+                    FROM asset.opac_visible_copies 
+                    WHERE copy_id = acp.id AND record = acn.record
+                ) ELSE TRUE END
+        GROUP BY acn.id, acp.status, aou.name, acn.label_sortkey, aou.id
+        WINDOW w AS (
+            ORDER BY 
+                COALESCE(
+                    CASE WHEN aou.id = p_ouid THEN -20000 END,
+                    CASE WHEN aou.id = p_pref_lib THEN -10000 END,
+                    (SELECT distance - 5000
+                        FROM actor.org_unit_descendants_distance(p_pref_lib) as x
+                        WHERE x.id = aou.id AND p_pref_lib IN (
+                            SELECT q.id FROM actor.org_unit_descendants(p_ouid) as q)),
+                    (SELECT e.distance FROM actor.org_unit_descendants_distance(p_ouid) as e WHERE e.id = aou.id),
+                    1000
+                ),
+                evergreen.rank_cp_status(acp.status)
+        )
+    ) AS ua
+    GROUP BY ua.id, ua.name, ua.label_sortkey
+    ORDER BY rank, ua.name, ua.label_sortkey
+    LIMIT (p_slimit -> 'acn')::INT
+    OFFSET (p_soffset -> 'acn')::INT;
+END;
+$_$;