Commit d4fa1159ac555212f5b978f6140b56b0ebdd49b4 added idempotency as a criteria for determining if retries must be done.
While, this change makes full sense, it breaks retrying Glacier's Complete Multipart Upload request. Indeed, Amazon did choose to specify this request as idempotent, while implementing it with POST, which is not.
As a workaround, nacx proposed:
We could move the idempotent logic to the default ioRetryHandler implementation, and let the Glacier API configure a custom one that did not take into account the method.
cf. discussion here