Allow file-ingest-triggered flush to skip waiting for write-stall clear #25
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…ar (facebook#4751) Summary: When write stall has already been triggered due to number of L0 files reaching threshold, file ingestion must proceed with its flush without waiting for the write stall condition to cleared by the compaction because compaction can wait for ingestion to finish (circular wait). In order to avoid this wait, we can set `FlushOptions.allow_write_stall` to be true (default is false). Setting it to false can cause deadlock. This can happen when the number of compaction threads is low. Considere the following ``` Time compaction_thread ingestion_thread | num_running_ingest_file_++ | while(num_running_ingest_file_>0){wait} | flush V ``` Pull Request resolved: facebook#4751 Differential Revision: D13343037 Pulled By: riversand963 fbshipit-source-id: d3b95938814af46ec4c463feff0b50c70bd8b23f
tbg
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Feb 12, 2019
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Summary:
When write stall has already been triggered due to number of L0 files reaching
threshold, file ingestion must proceed with its flush without waiting for the
write stall condition to cleared by the compaction because compaction can wait
for ingestion to finish (circular wait).
In order to avoid this wait, we can set
FlushOptions.allow_write_stallto betrue (default is false). Setting it to false can cause deadlock.
This can happen when the number of compaction threads is low.
Considere the following
Pull Request resolved: facebook#4751
Differential Revision: D13343037
Pulled By: riversand963
fbshipit-source-id: d3b95938814af46ec4c463feff0b50c70bd8b23f
This change is