operating system - Does Cassandra lock files in the data directory during reads/writes? -

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I know that cassandra can take snapshots when it is online This makes each snapshot subdirectory in the family directory , And the column inside it keeps a copy of the family. But I do not know if this is possible because there is no locking of the file at all, or if the snapshot instruction is waiting just to unlock one file before copying it.

Does anyone know how the cassandra contacts with files in the data directory? Apart from this, what behavior is dependent on the operating system? First of all, it is important to realize that all the files write the data directory of the case - once. No file is ever modified, it is made, then eventually merged with others, then it is removed. (It's a good idea to write the cassandra well, because all the disk access sequentials are for writing.)

The second thing is that taking a snapshot does not copy the file, it's a It makes hard links because it works because the files are read-only so no copy is necessary.

For these reasons, no file locking is necessary.

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