Details
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Improvement
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Status: Open
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Major
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Resolution: Unresolved
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3.4.0
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None
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None
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None
Description
Currently, data is accumulated in memory and written to the WAL on checkpoint only. This causes a write spike on checkpoint and does not utilize the HDFS write pipeline. The other extreme is writing to the WAL as soon as data arrives and then only flush in beforeCheckpoint. The downside of this is that when the same key is written many times, all duplicates will be in the WAL. Need to find a balances approach, that the user can potentially fine tune.