diff --git a/docker-compose.photoprism.yml b/docker-compose.photoprism.yml
index 663dfe3..11260b2 100644
--- a/docker-compose.photoprism.yml
+++ b/docker-compose.photoprism.yml
@@ -78,6 +78,13 @@ services:
       PHOTOPRISM_ORIGINALS_LIMIT: ${PP_ORIGINALS_LIMIT:-50000}
       PHOTOPRISM_HTTP_COMPRESSION: gzip
       PHOTOPRISM_LOG_LEVEL: ${PP_LOG_LEVEL:-info}
+      # Indexer concurrency. Defaults to NumCPU/2 (= 3 on a 6-core LXC),
+      # but each worker forks TF + ffmpeg + libvips so effective load is
+      # much higher — a fresh index of 1.2k photos on M0 pushed the LXC
+      # load to 50+ and starved sibling containers. Pin to a low value
+      # for shared hosts; raise on dedicated machines.
+      PHOTOPRISM_WORKERS: ${PP_WORKERS:-2}
+      PHOTOPRISM_INDEX_WORKERS: ${PP_INDEX_WORKERS:-${PP_WORKERS:-2}}
       # M0 safety: keep originals read-only. Flip to "false" in M2 when the
       # right-sidebar enables metadata edits and we want EXIF backwrite.
       PHOTOPRISM_READONLY: ${PP_READONLY:-true}