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Type: Investigation
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Resolution: Done
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Priority: Major - P3
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None
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Affects Version/s: None
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Component/s: None
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Labels:None
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Not Needed
(Note – this is mostly a rehash of the downstream changes in PM-1829. We are now re-enabling SBE as the default execution engine in 5.1, so this is a reminder to downstream teams that this is once again happening.)
The explain format has changed when SBE is used for a query. The details are documented here: https://docs.google.com/document/d/1d9IsNgkj5JDhJCcs88lCbPOR7iBvDHDUBTgLwK2qsZA/edit#bookmark=id.4iepecjh6rq9
The behavior of some expressions have changed between the classic and SBE engines as described in these documents:
https://docs.google.com/document/d/1HSMOF_Bn1kuG3Bsv2ATSN7QZixVsViIsO__vydWzdlw/edit
https://docs.google.com/spreadsheets/d/1z038wswqH2bdsKmtpGlGMYbe1LUy0krWs0AB2cr44bM/edit?pli=1#gid=0
We should consider adding something to the release notes about the new version coming with a new execution engine for eligible queries.
We expect SBE to be on by default, but we want to user to be able to opt out if they so choose. Users can use the internalQueryForceClassicEngine setParameter to disable SBE and only use the classic engine for all queries.
Description of Linked Ticket
Summary
Fix correctness issues such that we can enable SBE as the default execution engine in 5.1.
Motivation
A significant portion of the slot-based execution engine has been completed as part of PM-1647 Spike: Evaluate Slot-Based Query Execution and PM-1829 Slot-based execution for find, but it is not yet enabled by default. In order to ensure that the new engine will deliver performance benefits for our customers without destabilizing their clusters, the team would like to perform a staged rollout of the feature.
Cast of Characters
- Product Owner:
- Project Lead: Kyle Suarez
- Program Manager: Ana Meza
- Drivers Contact:
Documentation
Product Description
Scope Document
[Technical Design Document]: No Design