release/v20.11: opt(rollup): change the way rollups are done #7277
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ISSUE: In a load that has a lot of updations to a key, a lot of deltas accumulate over time. These keys are added to the batch for a rollup. Due to the lossy behavior of rollups, they get dropped while the dgraph is busy rolling up keys (that might have much smaller delta count). FIX: We now add keys to rollupBatch just after pushing the deltas over to badger. We now have a priority inside the keys that we rollup. The keys for which the deltas have increased up to a certain limit (hard-coded 500), we add it to high priority rollupKeyPool so that it has high chances to get rolled up and does not get dropped due to lossy behavior of rollups. Co-authored-by: Manish R Jain <manish@dgraph.io> Co-authored-by: NamanJain8 <jnaman806@gmail.com> (cherry picked from commit cbdc991)
jarifibrahim
approved these changes
Jan 12, 2021
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ISSUE:
In a load that has a lot of updations to a key, a lot of deltas accumulate over time. These keys are added to the batch for a rollup. Due to the lossy behavior of rollups, they get dropped while the dgraph is busy rolling up keys (that might have much smaller delta count).
FIX:
We now add keys to rollupBatch just after pushing the deltas over to badger.
We now have a priority inside the keys that we rollup. The keys for which the deltas have increased up to a certain limit (hard-coded 500), we add it to high priority rollupKeyPool so that it has high chances to get rolled up and does not get dropped due to lossy behavior of rollups.
Co-authored-by: Manish R Jain manish@dgraph.io
Co-authored-by: NamanJain8 jnaman806@gmail.com
(cherry picked from commit cbdc991)
This change is