1.5.2 is only 15 months old, which isn't all that long in 'enterprise time'.
Re:AWS Elasticsearch Service Woes
by happyslobro on Monday June 27, 2016 @01:18PM
(#11987663)
Forget enterprise time, it's about to be two major versions old in major version time, once v5 is official. Not sure what happened to v3 and v4, I think Elastic skipped them to get all of their products aligned to the same version.
Elastic says they don't backport fixes either, so in this case, it might be a good idea to stay near the leading edge of the release cycle.
The recent versions are far more stable and includes lots of efficiency in terms of memory usage.