From ae36ba80d7dcc90345eff90e4615734d916b55f1 Mon Sep 17 00:00:00 2001 From: "Bobby (Babak) Salamat" Date: Mon, 23 Oct 2017 10:47:32 -0700 Subject: [PATCH] Add performance implications of inter-pod affinity/anti-affinity (#5979) --- docs/concepts/configuration/assign-pod-node.md | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/docs/concepts/configuration/assign-pod-node.md b/docs/concepts/configuration/assign-pod-node.md index b7084cc2f7..964db539e5 100644 --- a/docs/concepts/configuration/assign-pod-node.md +++ b/docs/concepts/configuration/assign-pod-node.md @@ -157,6 +157,10 @@ like node, rack, cloud provider zone, cloud provider region, etc. You express it key for the node label that the system uses to denote such a topology domain, e.g. see the label keys listed above in the section [Interlude: built-in node labels](#interlude-built-in-node-labels). +**Note:** Inter-pod affinity and anti-affinity require substantial amount of +processing which can slow down scheduling in large clusters significantly. We do +not recommend using them in clusters larger than several hundred nodes. + As with node affinity, there are currently two types of pod affinity and anti-affinity, called `requiredDuringSchedulingIgnoredDuringExecution` and `preferredDuringSchedulingIgnoredDuringExecution` which denote "hard" vs. "soft" requirements. See the description in the node affinity section earlier.