How to limit the memory used by voltdb

Question

I didn't see any properties for limiting the size of memory used by voltdb,when I config voltdb, so I want to ask: Can I config the max size of memory used by voltdb? If I can, how to config?Where is the configuration file? Can voltdb work in mixed mode of memory and disk?

Answer 1

You can set VoltDB to pause when a certain memory limit is reached. You do this in the configuration file that you start VoltDB with, specifically within the resource monitor section. It would look something like this:

<systemsettings>
  <resourcemonitor frequency="30">
    <memorylimit size="70%" alert="60%"/>
  </resourcemonitor>
</systemsettings>

You can read more about it in the VoltDB documentation: https://docs.voltdb.com/AdminGuide/MonitorSysResource.php

As for your other question, VoltDB doesn't work in a mixed mode of memory and disk. In fact, it is highly recommended that swapping be disabled. You should review the memory management optimizations listed here: https://docs.voltdb.com/AdminGuide/adminmemmgt.php

Full disclosure: I work at VoltDB.