From c7b0150834fb878a86a52e615b303dc00a66fe32 Mon Sep 17 00:00:00 2001
From: tobi <tobi.smethurst@protonmail.com>
Date: Fri, 26 Sep 2025 17:14:42 +0200
Subject: [PATCH] whew

---
 .../20250415111056_thread_all_statuses.go     | 79 +++++--------------
 1 file changed, 20 insertions(+), 59 deletions(-)

diff --git a/internal/db/bundb/migrations/20250415111056_thread_all_statuses.go b/internal/db/bundb/migrations/20250415111056_thread_all_statuses.go
index 86fbbd49f..bfa4dd84f 100644
--- a/internal/db/bundb/migrations/20250415111056_thread_all_statuses.go
+++ b/internal/db/bundb/migrations/20250415111056_thread_all_statuses.go
@@ -24,6 +24,7 @@ import (
 	"reflect"
 	"slices"
 	"strings"
+	"time"
 
 	"code.superseriousbusiness.org/gotosocial/internal/db"
 	newmodel "code.superseriousbusiness.org/gotosocial/internal/db/bundb/migrations/20250415111056_thread_all_statuses/new"
@@ -34,7 +35,6 @@ import (
 	"code.superseriousbusiness.org/gotosocial/internal/log"
 	"code.superseriousbusiness.org/gotosocial/internal/util/xslices"
 	"github.com/uptrace/bun"
-	"github.com/uptrace/bun/dialect"
 )
 
 func init() {
@@ -62,45 +62,8 @@ func init() {
 			return gtserror.Newf("error adding statuses column thread_id_new: %w", err)
 		}
 
-		// Create an index on thread_id_new so we can keep
-		// track of it as we update, and use it to avoid
-		// selecting statuses we've already updated.
-		//
-		// We'll remove this at the end of the migration.
-		log.Info(ctx, "creating temporary thread_id_new index")
-		if db.Dialect().Name() == dialect.PG {
-			// On Postgres we can use a partial index
-			// to indicate we only care about default
-			// value thread IDs (ie., not set yet).
-			if _, err := db.NewCreateIndex().
-				Table("statuses").
-				Index("statuses_thread_id_new_idx").
-				Column("thread_id_new").
-				Where("? = ?", bun.Ident("thread_id_new"), id.Lowest).
-				Exec(ctx); err != nil {
-				return gtserror.Newf("error creating temporary thread_id_new index: %w", err)
-			}
-		} else {
-			// On SQLite we can use an index expression
-			// to do the same thing. While we *can* use
-			// a partial index for this, an index expression
-			// is magnitudes faster. Databases!
-			if _, err := db.NewCreateIndex().
-				Table("statuses").
-				Index("statuses_thread_id_new_idx").
-				ColumnExpr("? = ?", bun.Ident("thread_id_new"), id.Lowest).
-				Exec(ctx); err != nil {
-				return gtserror.Newf("error creating temporary thread_id_new index: %w", err)
-			}
-		}
-
-		// Attempt to merge any sqlite write-ahead-log.
-		if err := doWALCheckpoint(ctx, db); err != nil {
-			return err
-		}
-
 		var sr statusRethreader
-		var updatedRows int64
+		var updatedRowsTotal int64
 		var maxID string
 		var statuses []*oldmodel.Status
 
@@ -116,21 +79,20 @@ func init() {
 
 		log.Warnf(ctx, "migrating %d statuses, this may take a *long* time", total)
 		for {
+			start := time.Now()
 
 			// Reset slice.
 			clear(statuses)
 			statuses = statuses[:0]
 
-			// Select IDs of next batch, paging down
-			// and skipping statuses to which we've
-			// already allocated a (new) thread ID.
+			// Select IDs of next
+			// batch, paging down.
 			if err := db.NewSelect().
 				Model(&statuses).
 				Column("id").
-				Where("? = ?", bun.Ident("thread_id_new"), id.Lowest).
 				Where("? < ?", bun.Ident("id"), maxID).
 				OrderExpr("? DESC", bun.Ident("id")).
-				Limit(200).
+				Limit(250).
 				Scan(ctx); err != nil && !errors.Is(err, sql.ErrNoRows) {
 				return gtserror.Newf("error selecting unthreaded statuses: %w", err)
 			}
@@ -146,13 +108,15 @@ func init() {
 			maxID = statuses[l-1].ID
 
 			// Rethread each selected status in a transaction.
+			var updatedRowsThisBatch int64
 			if err := db.RunInTx(ctx, nil, func(ctx context.Context, tx bun.Tx) error {
 				for _, status := range statuses {
 					n, err := sr.rethreadStatus(ctx, tx, status)
 					if err != nil {
 						return gtserror.Newf("error rethreading status %s: %w", status.URI, err)
 					}
-					updatedRows += n
+					updatedRowsThisBatch += n
+					updatedRowsTotal += n
 				}
 
 				return nil
@@ -160,22 +124,26 @@ func init() {
 				return err
 			}
 
-			// Show percent migrated.
+			// Show current speed + percent migrated.
 			//
-			// Will maybe end up wonky due to approximations
+			// Percent may end up wonky due to approximations
 			// and batching, so show a generic message at 100%.
-			percentDone := (float64(updatedRows) / float64(total)) * 100
+			timeTaken := time.Since(start).Milliseconds()
+			msPerRow := float64(timeTaken) / float64(updatedRowsThisBatch)
+			rowsPerMs := float64(1) / float64(msPerRow)
+			rowsPerSecond := 1000 * rowsPerMs
+			percentDone := (float64(updatedRowsTotal) / float64(total)) * 100
 			if percentDone <= 100 {
 				log.Infof(
 					ctx,
-					"[updated %d rows] migrated approx. %.2f%% of statuses",
-					updatedRows, percentDone,
+					"[updated %d total rows, now @ ~%.0f rows/s] done ~%.2f%% of statuses",
+					updatedRowsTotal, rowsPerSecond, percentDone,
 				)
 			} else {
 				log.Infof(
 					ctx,
-					"[updated %d rows] almost done migrating... ",
-					updatedRows,
+					"[updated %d total rows, now @ ~%.0f rows/s] almost done... ",
+					updatedRowsTotal, rowsPerSecond,
 				)
 			}
 		}
@@ -185,13 +153,6 @@ func init() {
 			return err
 		}
 
-		log.Info(ctx, "dropping temporary thread_id_new index")
-		if _, err := db.NewDropIndex().
-			Index("statuses_thread_id_new_idx").
-			Exec(ctx); err != nil {
-			return gtserror.Newf("error dropping temporary thread_id_new index: %w", err)
-		}
-
 		log.Info(ctx, "dropping old thread_to_statuses table")
 		if _, err := db.NewDropTable().
 			Table("thread_to_statuses").