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javajava-8chroniclechronicle-map

OpenHFT Chronicle Map frequency of persist on to the disk

I had few questions regarding openHFT chronicle map.

  1. How often does chronicle map persist from memory to disk.
  2. Is this time configurable?
  3. If JVM process with chronicle map crashes. Does the data in off heap memory gets flushed automatically?
  4. Can someone point me to correct resources that are available for above questions?

Thank you

Solution

    1. This is determined by the OS, it is between 5 and 30 seconds by default up to a maximum of 10% of the main memory not being written to disk.

    2. dirtytime_expire_seconds and dirty_expire_centisecs https://docs.kernel.org/admin-guide/sysctl/vm.html

    3. The data is flushed by the OS so as long as this keeps running for another 30 seconds, it should be flushed.

    4. In short, it's controlled by your OS.