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[PDS-243785] Count Attempted Hosts per DC #5903
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Generate changelog in
|
Jolyon-S
approved these changes
Feb 10, 2022
| .filter(attempts -> Objects.equals( | ||
| attempts, | ||
| maximumAttemptsPerDatacenter.orElseThrow(() -> new SafeIllegalStateException( | ||
| "Unexpectedly could not find the max attempts per " + "datacenter")))) |
…into jkong/count-the-cost-2
|
Released 0.542.0 |
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Goals (and why):
#5902 introduces a consideration for datacenters when choosing hosts to retry on. However, this is still vulnerable to an edge case (h/t @zpear): if a node in DC 1 bounces while it's being attempted and we go to DC 2, then it's possible that we retry exclusively in DC 2 (i.e., we only ever made a single attempt in DC 1).
==COMMIT_MSG==
Cassandra host routing now distributes retry attempts between datacenters as evenly as possible.
==COMMIT_MSG==
Implementation Description (bullets):
Ban hosts from the datacenter that has had the most hosts attempted.
Testing (What was existing testing like? What have you done to improve it?): Added new tests
Concerns (what feedback would you like?): Did I accidentally break anything?
Where should we start reviewing?: small
Priority (whenever / two weeks / yesterday): 🔥