pref: Reduce the number of DescribeImages calls

[engedaam]

Fixes #5997

Description

• Karpenter currently does not have any locking mechanism during its read and write operation for AMIs that are stored in the cache. Adding in locks to synchronize the cache for identical AMISelectorTerms
• The DescribeImages API does not filter out AMIs before fetching AMIs by tags. This will result in the DescribeImages API sending empty pages(This is currently expected behavior). The best mitigation here will for Karpenter to increases page sizes to reduce the number of request that are made.

How was this change tested?

• Result from testing
• I had 20 EC2NodeClass with Identical AMISelectorTerms set

  amiSelectorTerms:
  - tags:
      testing: aengeda

• Number of DescribeImages call from main: 1604
• Number of DescribeImages call from with Improvements: 79

Does this change impact docs?

• Yes, PR includes docs updates
• Yes, issue opened: #
• No

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

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[coveralls]

Pull Request Test Coverage Report for Build 8916099157

Details

• 4 of 4 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.008%) to 82.111%

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Totals
Change from base Build 8914365316:	0.008%
Covered Lines:	5407
Relevant Lines:	6585

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💛 - Coveralls

[jonathan-innis]

LGTM 🚀

[engedaam]

/karpenter snapshot

[github-actions]

Snapshot successfully published to oci://021119463062.dkr.ecr.us-east-1.amazonaws.com/karpenter/snapshot/karpenter:0-4e77f50717a5a9fce799ff54414ebe8a66456998.
To install you must login to the ECR repo with an AWS account:

aws ecr get-login-password --region us-east-1 | docker login --username AWS --password-stdin 021119463062.dkr.ecr.us-east-1.amazonaws.com

helm upgrade --install karpenter oci://021119463062.dkr.ecr.us-east-1.amazonaws.com/karpenter/snapshot/karpenter --version "0-4e77f50717a5a9fce799ff54414ebe8a66456998" --namespace "kube-system" --create-namespace \
  --set "settings.clusterName=${CLUSTER_NAME}" \
  --set "settings.interruptionQueue=${CLUSTER_NAME}" \
  --set controller.resources.requests.cpu=1 \
  --set controller.resources.requests.memory=1Gi \
  --set controller.resources.limits.cpu=1 \
  --set controller.resources.limits.memory=1Gi \
  --wait