stuff

crates/db_perf/src/main.rs

@@ -12,7 +12,7 @@ use lemmy_db_schema::{
   utils::{
     build_db_pool,
     get_conn,
-    series::{self, ValuesFromSeries},
+    series::{self, ValuesFromSeries}, DbConn, DbPool,
   },
   SortType,
 };
@@ -31,8 +31,10 @@ struct CmdArgs {
   people: NonZeroU32,
   #[arg(long, default_value_t = 100000.try_into().unwrap())]
   posts: NonZeroU32,
+  #[arg(long, default_value_t = 0)]
+  read_post_pages: u32,
   #[arg(long)]
-  read_posts: bool,
+  explain_insertions: bool,
 }
 
 #[tokio::main]
@@ -41,6 +43,14 @@ async fn main() -> LemmyResult<()> {
   let pool = &build_db_pool().await?;
   let pool = &mut pool.into();
 
+  let conn = &mut get_conn(pool).await?;
+  if args.explain_insertions {
+    sql_query("SET auto_explain.log_min_duration = 0")
+      .execute(conn)
+      .await?;
+  }
+  let pool = &mut conn.into();
+
   let instance = Instance::read_or_create(pool, "reddit.com".to_owned()).await?;
 
   println!("🫃 creating {} people", args.people);
@@ -121,9 +131,9 @@ async fn main() -> LemmyResult<()> {
     .await?;
   let pool = &mut conn.into();
   
-  if args.read_posts {
+  {
     let mut page_after = None;
-    for page_num in 1..=2 {
+    for page_num in 1..=args.read_post_pages {
       println!(
         "👀 getting page {page_num} of posts (pagination cursor used: {})",
         page_after.is_some()
@@ -138,19 +148,31 @@ async fn main() -> LemmyResult<()> {
       }
       .list(pool)
       .await?;
-      if let Some(post_view) = post_views.into_iter().last() {
-        println!("👀 getting pagination cursor data for next page ");
-        let cursor_data = PaginationCursor::after_post(&post_view).read(pool).await?;
-        page_after = Some(cursor_data);
-      } else {
-        break;
-      }
+    if let Some(post_view) = post_views.into_iter().last() {
+      println!("👀 getting pagination cursor data for next page");
+      let cursor_data = PaginationCursor::after_post(&post_view).read(pool).await?;
+      page_after = Some(cursor_data);
+    } else {
+      println!("🚫 reached empty page");
+      break;
+    }
     }
   }
   
+  // TODO show this path when there's an error
   if let Ok(path) = std::env::var("PGDATA") {
     println!("🪵 query plans written in {path}/log");
   }
   
   Ok(())
 }
+
+async fn conn_with_auto_explain<'a, 'b: 'a>(pool: &'a mut DbPool<'b>) -> LemmyResult<DbConn<'a>> {
+  let mut conn = get_conn(pool).await?;
+
+  sql_query("SET auto_explain.log_min_duration = 0")
+    .execute(&mut conn)
+    .await?;
+
+  Ok(conn)
+}

migrations/2023-12-19-210053_tolerable-batch-insert-speed/down.sql

@@ -30,6 +30,46 @@ CREATE OR REPLACE TRIGGER post_aggregates_post
     FOR EACH ROW
     EXECUTE PROCEDURE post_aggregates_post ();
 
+CREATE OR REPLACE TRIGGER community_aggregates_post_count
+    AFTER INSERT OR DELETE OR UPDATE OF removed,
+    deleted ON post
+    FOR EACH ROW
+    EXECUTE PROCEDURE community_aggregates_post_count ();
+
+DROP FUNCTION IF EXISTS community_aggregates_post_count_insert CASCADE;
+
+DROP FUNCTION IF EXISTS community_aggregates_post_update CASCADE;
+
+DROP FUNCTION IF EXISTS site_aggregates_post_update CASCADE;
+
+DROP FUNCTION IF EXISTS person_aggregates_post_insert CASCADE;
+
+CREATE OR REPLACE FUNCTION site_aggregates_post_insert ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    IF (was_restored_or_created (TG_OP, OLD, NEW)) THEN
+        UPDATE
+            site_aggregates sa
+        SET
+            posts = posts + 1
+        FROM
+            site s
+        WHERE
+            sa.site_id = s.id;
+    END IF;
+    RETURN NULL;
+END
+$$;
+
+CREATE OR REPLACE TRIGGER site_aggregates_post_insert
+    AFTER INSERT OR UPDATE OF removed,
+    deleted ON post
+    FOR EACH ROW
+    WHEN (NEW.local = TRUE)
+    EXECUTE PROCEDURE site_aggregates_post_insert ();
+
 CREATE OR REPLACE FUNCTION generate_unique_changeme ()
     RETURNS text
     LANGUAGE sql
@@ -38,5 +78,11 @@ CREATE OR REPLACE FUNCTION generate_unique_changeme ()
         'http://changeme.invalid/' || substr(md5(random()::text), 0, 25);
 $$;
 
+CREATE TRIGGER person_aggregates_post_count
+    AFTER INSERT OR DELETE OR UPDATE OF removed,
+    deleted ON post
+    FOR EACH ROW
+    EXECUTE PROCEDURE person_aggregates_post_count ();
+
 DROP SEQUENCE IF EXISTS changeme_seq;
 

migrations/2023-12-19-210053_tolerable-batch-insert-speed/up.sql

@@ -1,5 +1,6 @@
--- Change post_aggregates trigger to run once per statement instead of once per row.
--- The trigger doesn't need to handle deletion because the post_id column has ON DELETE CASCADE.
+-- Change triggers to run once per statement instead of once per row
+
+-- post_aggregates_post trigger doesn't need to handle deletion because the post_id column has ON DELETE CASCADE
 
 CREATE OR REPLACE FUNCTION post_aggregates_post ()
     RETURNS TRIGGER
@@ -8,25 +9,128 @@ CREATE OR REPLACE FUNCTION post_aggregates_post ()
 BEGIN
     INSERT INTO post_aggregates (post_id, published, newest_comment_time, newest_comment_time_necro, community_id, creator_id, instance_id)
     SELECT
-        new_post.id,
-        new_post.published,
-        new_post.published,
-        new_post.published,
-        new_post.community_id,
-        new_post.creator_id,
-        (SELECT community.instance_id FROM community WHERE community.id = new_post.community_id LIMIT 1)
+        id,
+        published,
+        published,
+        published,
+        community_id,
+        creator_id,
+        (SELECT community.instance_id FROM community WHERE community.id = community_id LIMIT 1)
     FROM
         new_post;
     RETURN NULL;
 END
 $$;
 
+CREATE OR REPLACE FUNCTION community_aggregates_post_count_insert ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    UPDATE community_aggregates
+    SET posts = posts + post_group.count
+    FROM (SELECT community_id, count(*) FROM new_post GROUP BY community_id) post_group
+    WHERE community_aggregates.community_id = post_group.community_id;
+    RETURN NULL;
+END
+$$;
+
+CREATE OR REPLACE FUNCTION person_aggregates_post_insert ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    UPDATE person_aggregates
+    SET post_count = post_count + post_group.count
+    FROM (SELECT creator_id, count(*) FROM new_post GROUP BY creator_id) post_group
+    WHERE person_aggregates.person_id = post_group.creator_id;
+    RETURN NULL;
+END
+$$;
+
 CREATE OR REPLACE TRIGGER post_aggregates_post
     AFTER INSERT ON post
     REFERENCING NEW TABLE AS new_post
     FOR EACH STATEMENT
     EXECUTE PROCEDURE post_aggregates_post ();
 
+-- Don't run old trigger for insert
+
+CREATE OR REPLACE TRIGGER community_aggregates_post_count
+    AFTER DELETE OR UPDATE OF removed,
+    deleted ON post
+    FOR EACH ROW
+    EXECUTE PROCEDURE community_aggregates_post_count ();
+
+CREATE OR REPLACE TRIGGER community_aggregates_post_count_insert
+    AFTER INSERT ON post
+    REFERENCING NEW TABLE AS new_post
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE community_aggregates_post_count_insert ();
+
+DROP FUNCTION IF EXISTS site_aggregates_community_delete CASCADE;
+
+CREATE OR REPLACE FUNCTION site_aggregates_post_update ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    IF (was_restored_or_created (TG_OP, OLD, NEW)) THEN
+        UPDATE
+            site_aggregates sa
+        SET
+            posts = posts + 1
+        FROM
+            site s
+        WHERE
+            sa.site_id = s.id;
+    END IF;
+    RETURN NULL;
+END
+$$;
+
+CREATE OR REPLACE FUNCTION site_aggregates_post_insert ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    UPDATE
+        site_aggregates sa
+    SET
+        posts = posts + (SELECT count(*) FROM new_post)
+    FROM
+        site s
+    WHERE
+        sa.site_id = s.id;
+    RETURN NULL;
+END
+$$;
+
+CREATE OR REPLACE TRIGGER site_aggregates_post_update
+    AFTER UPDATE OF removed,
+    deleted ON post
+    FOR EACH ROW
+    WHEN (NEW.local = TRUE)
+    EXECUTE PROCEDURE site_aggregates_post_update ();
+
+CREATE OR REPLACE TRIGGER site_aggregates_post_insert
+    AFTER INSERT ON post
+    REFERENCING NEW TABLE AS new_post
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE site_aggregates_post_insert ();
+
+CREATE OR REPLACE TRIGGER person_aggregates_post_count
+    AFTER DELETE OR UPDATE OF removed,
+    deleted ON post
+    FOR EACH ROW
+    EXECUTE PROCEDURE person_aggregates_post_count ();
+
+CREATE OR REPLACE TRIGGER person_aggregates_post_insert
+    AFTER INSERT ON post
+    REFERENCING NEW TABLE AS new_post
+    FOR EACH STATEMENT
+    EXECUTE PROCEDURE person_aggregates_post_insert ();
+
 -- Avoid running hash function and random number generation for default ap_id
 
 CREATE SEQUENCE IF NOT EXISTS changeme_seq AS bigint CYCLE;

scripts/start_dev_db.sh

@@ -2,12 +2,14 @@
 
 export PGDATA="$PWD/dev_pgdata"
 export PGHOST=$PWD
-export LEMMY_DATABASE_URL="postgresql://lemmy:password@/lemmy?host=$PWD"
+export DATABASE_URL="postgresql://lemmy:password@/lemmy?host=$PWD"
+export LEMMY_DATABASE_URL=$DATABASE_URL
 
 # If cluster exists, stop the server and delete the cluster
 if [[ -d $PGDATA ]]
 then
   # Only stop server if it is running
+  pg_status_exit_code=0
   (pg_ctl status > /dev/null) || pg_status_exit_code=$?
   if [[ ${pg_status_exit_code} -ne 3 ]]
   then
@@ -27,7 +29,9 @@ config_args=(
 
   # Allow auto_explain to be turned on
   -c session_preload_libraries=auto_explain
-  #-c auto_explain.log_min_duration=0
+
+  # Log triggers
+  -c auto_explain.log_nested_statements=on
 
   # Include actual row amounts and run times for query plan nodes
   -c auto_explain.log_analyze=on