nifi/nifi-commons/nifi-write-ahead-log/src
Mark Payne 96ed405d70 NIFI-3356: Initial implementation of writeahead provenance repository
- The idea behind NIFI-3356 was to improve the efficiency and throughput of the Provenance Repository, as it is often the bottleneck. While testing the newly designed repository,
  a handful of other, fairly minor, changes were made to improve efficiency as well, as these came to light when testing the new repository:

- Use a BufferedOutputStream within StandardProcessSession (via a ClaimCache abstraction) in order to avoid continually writing to FileOutputStream when writing many small FlowFiles
- Updated threading model of MinimalLockingWriteAheadLog - now performs serialization outside of lock and writes to a 'synchronized' OutputStream
- Change minimum scheduling period for components from 30 microseconds to 1 nanosecond. ScheduledExecutor is very inconsistent with timing of task scheduling. With the bored.yield.duration
  now present, this value doesn't need to be set to 30 microseconds. This was originally done to avoid processors that had no work from dominating the CPU. However, now that we will yield
  when processors have no work, this results in slowing down processors that are able to perform work.
- Allow nifi.properties to specify multiple directories for FlowFile Repository
- If backpressure is engaged while running a batch of sessions, then stop batch processing earlier. This helps FlowFiles to move through the system much more smoothly instead of the
  herky-jerky queuing that we previously saw at very high rates of FlowFiles.
- Added NiFi PID to log message when starting nifi. This was simply an update to the log message that provides helpful information.

NIFI-3356: Fixed bug in ContentClaimWriteCache that resulted in data corruption and fixed bug in RepositoryConfiguration that threw exception if cache warm duration was set to empty string

NIFI-3356: Fixed NPE

NIFI-3356: Added debug-level performance monitoring

NIFI-3356: Updates to unit tests that failed after rebasing against master

NIFI-3356: Incorporated PR review feedback

NIFI-3356: Fixed bug where we would delete index directories that are still in use; also added additional debug logging and a simple util class that can be used to textualize provenance event files - useful in debugging

This closes #1493
2017-02-22 12:40:06 -05:00
..
main/java/org/wali NIFI-3356: Initial implementation of writeahead provenance repository 2017-02-22 12:40:06 -05:00
test/java/org/wali NIFI-3356: Initial implementation of writeahead provenance repository 2017-02-22 12:40:06 -05:00