File fix-for-ec2-rate-limit-failures.patch of Package salt.8688

From b0273e150b29fb44d72246918792117b485441de Mon Sep 17 00:00:00 2001
From: Daniel Wallace <gtmanfred@users.noreply.github.com>
Date: Wed, 25 Apr 2018 11:13:15 -0500
Subject: [PATCH] Fix for EC2 Rate Limit Failures

Fix for ec2 rate limit failures described here: https://bugzilla.suse.com/show_bug.cgi?id=1088888
---
 salt/utils/aws.py | 22 ++++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/salt/utils/aws.py b/salt/utils/aws.py
index 059450e7ca..912f1466ba 100644
--- a/salt/utils/aws.py
+++ b/salt/utils/aws.py
@@ -20,6 +20,7 @@ import hmac
 import logging
 import salt.config
 import re
+import random
 from salt.ext import six
 
 # Import Salt libs
@@ -442,8 +443,9 @@ def query(params=None, setname=None, requesturl=None, location=None,
         )
         headers = {}
 
-    attempts = 5
-    while attempts > 0:
+    MAX_RETRIES = 6
+    attempts = 0
+    while attempts < MAX_RETRIES:
         log.debug('AWS Request: %s', requesturl)
         log.trace('AWS Request Parameters: %s', params_with_headers)
         try:
@@ -461,15 +463,23 @@ def query(params=None, setname=None, requesturl=None, location=None,
 
             # check to see if we should retry the query
             err_code = data.get('Errors', {}).get('Error', {}).get('Code', '')
-            if attempts > 0 and err_code and err_code in AWS_RETRY_CODES:
-                attempts -= 1
+            if attempts < MAX_RETRIES and err_code and err_code in AWS_RETRY_CODES:
+                attempts += 1
                 log.error(
                     'AWS Response Status Code and Error: [%s %s] %s; '
                     'Attempts remaining: %s',
                     exc.response.status_code, exc, data, attempts
                 )
-                # Wait a bit before continuing to prevent throttling
-                time.sleep(2)
+                # backoff an exponential amount of time to throttle requests
+                # during "API Rate Exceeded" failures as suggested by the AWS documentation here:
+                # https://docs.aws.amazon.com/AWSEC2/latest/APIReference/query-api-troubleshooting.html
+                # and also here:
+                # https://docs.aws.amazon.com/general/latest/gr/api-retries.html
+                # Failure to implement this approach results in a failure rate of >30% when using salt-cloud with
+                # "--parallel" when creating 50 or more instances with a fixed delay of 2 seconds.
+                # A failure rate of >10% is observed when using the salt-api with an asyncronous client
+                # specified (runner_async).
+                time.sleep(random.uniform(1, 2**attempts))
                 continue
 
             log.error(
-- 
2.13.6