perf(ebooks): allow large backfill worker pools

internal/ebooks/enrichment.go

@@ -31,8 +31,9 @@ import (
 const (
 	ebookMetadataImageProviderID = "ebook-metadata"
 
-	defaultEnrichBatchSize = 50
+	defaultEnrichBatchSize = 5000
 	defaultEnrichWorkers   = 4
+	maxEnrichWorkers       = 5000
 
 	defaultEnrichmentItemTimeout = 2 * time.Minute
 )
@@ -69,8 +70,8 @@ func ebookEnrichWorkers() int {
 			n = parsed
 		}
 	}
-	if n > defaultEnrichBatchSize {
-		n = defaultEnrichBatchSize
+	if n > maxEnrichWorkers {
+		n = maxEnrichWorkers
 	}
 	return n
 }

internal/ebooks/enrichment_test.go

@@ -69,9 +69,14 @@ func TestEbookEnrichWorkersFromEnv(t *testing.T) {
 		t.Fatalf("ebookEnrichWorkers() with zero = %d, want default %d", got, defaultEnrichWorkers)
 	}
 
-	t.Setenv("SILO_EBOOK_ENRICH_WORKERS", "999")
-	if got := ebookEnrichWorkers(); got != defaultEnrichBatchSize {
-		t.Fatalf("ebookEnrichWorkers() capped = %d, want %d", got, defaultEnrichBatchSize)
+	t.Setenv("SILO_EBOOK_ENRICH_WORKERS", "5000")
+	if got := ebookEnrichWorkers(); got != 5000 {
+		t.Fatalf("ebookEnrichWorkers() = %d, want 5000", got)
+	}
+
+	t.Setenv("SILO_EBOOK_ENRICH_WORKERS", "9999")
+	if got := ebookEnrichWorkers(); got != maxEnrichWorkers {
+		t.Fatalf("ebookEnrichWorkers() capped = %d, want %d", got, maxEnrichWorkers)
 	}
 }