HDDS-14194. Make streaming write SYNC configurable #9533
+17
−4
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What changes were proposed in this pull request?
See BlockDataStreamOutput#needSync, currently SYNC is never used and therefore we might not be sure when the data is actually flushed to the disk (see StreamDataChannelBase#force which will invoke FileChannel#force(false) to flush the data to the underlying storage)
We can create a configuration to allow SYNC, which is disabled by default to preserve compatibility.
We also might want to revisit whether we should make SYNC to be a client-side or server-side. The concern is if a client is misconfigured, it might cause a lot of sync on the DN which will cause higher latencies.
What is the link to the Apache JIRA
https://issues.apache.org/jira/browse/HDDS-14194
How was this patch tested?