From 62b872ba382082fe0b7f2e6179c534eba1efb455 Mon Sep 17 00:00:00 2001 From: Kensei Nakada Date: Fri, 24 May 2024 14:40:10 +0900 Subject: [PATCH] Elaborate the doc of minReplica (#404) --- docs/horizontal.md | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/docs/horizontal.md b/docs/horizontal.md index 4ab2236f..49d7f78b 100644 --- a/docs/horizontal.md +++ b/docs/horizontal.md @@ -48,6 +48,14 @@ max{replica numbers at the same time} * MinReplicasRecommendationMultiplier (refer to [admin-guide.md](./admin-guide.md) about each parameter) +#### Why does MinReplicas have to be changed like this? + +Supposing your web frontend is down, your backend app Pods would be scaled in because it receives no traffic. +But, when your web frontend is back, the huge traffic that the backend app usually handles would come again, +and if the backend had been scaled in too much, it could be overwhelmed easily. + +To prevent this kind of issue like domino, Tortoise sets MinReplicas like above so that it can keep the replica number to some extend, preventing too much scaling in. + ### Target utilization Target utilization is calculated by: