HDFS-16574. Reduces the time it takes once to hold FSNamesystem write lock to remove blocks associated with dead datanodes #4322
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…ove blocks associated with dead datanodes
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jojochuang
reviewed
Jun 28, 2022
| int numBlocksRemovedPerLock = 0; | ||
| while(it.hasNext()) { | ||
| if (numBlocksRemovedPerLock >= numBlocksPerRemove) { | ||
| namesystem.writeUnlock(); |
Contributor
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How is this code tested? It's usually not wise to release the namenode lock arbitrarily.
Looking at the code, the iterator is not thread-safe and there is no guarantee the iterator will be able to get to the next one after the lock is re-acquired.
jojochuang
reviewed
Jun 28, 2022
| if (numBlocksRemovedPerLock >= numBlocksPerRemove) { | ||
| namesystem.writeUnlock(); | ||
| try { | ||
| LOG.debug("Yielded lock during removing blocks associated to the dead datanode"); //释放锁，并sleep 500ns（1 ns = 10-9 s） |
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Please use English for comments.
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We're closing this stale PR because it has been open for 100 days with no activity. This isn't a judgement on the merit of the PR in any way. It's just a way of keeping the PR queue manageable. |
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JIRA: HDFS-16574
Reduces the time it takes once to hold FSNamesystem write lock to remove blocks associated with dead datanodes.