From b1e0b4251bf252042623c8cd1c27daf5d2f66271 Mon Sep 17 00:00:00 2001
From: Ben Bangert <100193+bbangert@users.noreply.github.com>
Date: Fri, 8 Mar 2024 11:30:00 -0800
Subject: [PATCH] feat: add rate limit scaling to delete script Because:

* We want to auto-scale our queueing.

This commit:

* Adds a scaling policy to the delete script.
---
 .../scripts/delete-unverified-accounts.ts        | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/packages/fxa-auth-server/scripts/delete-unverified-accounts.ts b/packages/fxa-auth-server/scripts/delete-unverified-accounts.ts
index 4c21b7c7d17..f6ce09da62d 100644
--- a/packages/fxa-auth-server/scripts/delete-unverified-accounts.ts
+++ b/packages/fxa-auth-server/scripts/delete-unverified-accounts.ts
@@ -235,9 +235,23 @@ const init = async () => {
       return 0;
     }
 
-    const queue = new PQueue({ interval: 1000, intervalCap: taskLimit });
+    // Scaling suggestion is 500/5/50 rule, may start at 500/sec, and increase every 5 minutes by 50%.
+    // They also note increased latency may occur past 1000/sec, so we stop increasing as we approach that.
+    const scaleUpIntervalMins = 6;
+    let lastScaleUp = Date.now();
+    let rateLimit = taskLimit;
+    let queue = new PQueue({ interval: 1000, intervalCap: rateLimit });
 
     for (const x of accounts) {
+      if (
+        rateLimit < 950 &&
+        Date.now() - lastScaleUp > scaleUpIntervalMins * 60 * 1000
+      ) {
+        await queue.onIdle();
+        lastScaleUp = Date.now();
+        rateLimit = Math.floor(rateLimit * 1.5);
+        queue = new PQueue({ interval: 1000, intervalCap: rateLimit });
+      }
       queue.add(async () => {
         try {
           const result = await accountDeleteManager.enqueue({