diff --git a/helm-overrides/gke-toolshed-prd-usc1/victoria-metrics-single/custom-values.yaml b/helm-overrides/gke-toolshed-prd-usc1/victoria-metrics-single/custom-values.yaml
index 2875db8..7b389d9 100644
--- a/helm-overrides/gke-toolshed-prd-usc1/victoria-metrics-single/custom-values.yaml
+++ b/helm-overrides/gke-toolshed-prd-usc1/victoria-metrics-single/custom-values.yaml
@@ -1,9 +1,21 @@
 victoria-metrics-single:
   server:
-    # 7 days rather than the chart's month: this cluster exists to prove a
+    # 3 days rather than the chart's month: this cluster exists to prove a
     # pipeline, and every extra day is disk against the project's 250GB SSD
-    # quota, which every standard-rwo volume in the cluster shares.
-    retentionPeriod: "7d"
+    # quota, which every standard-rwo volume in the cluster shares. Three
+    # days still spans a weekend, which is the window that matters for
+    # working out what happened to something overnight.
+    #
+    # Down from 7d. Note what this does and does not do: it reclaims disk as
+    # old partitions are dropped, and shrinks the index a little, but it
+    # does NOT reduce the memory this needs to run. That tracks active time
+    # series and cache size, neither of which depends on how long data is
+    # kept — which is why the limit above had to be raised rather than this
+    # lowered when it started OOM-killing on restart. The lever for memory
+    # is scrape cardinality: several targets here carry more than forty
+    # labels per series (see the maxLabelsPerTimeseries warnings in its
+    # log), and dropping labels there would cut series count directly.
+    retentionPeriod: "3d"
 
     persistentVolume:
       storageClassName: standard-rwo