ConcurrentModificationException when requesting the database size

[jbilcke]

OrientDB Version: v2.2.2

Java Version: Java 8 Update 111

OS: macOS Sierra 10.12.2

My app uses OrientJS to communicate with OrientDB using the REST API.
Their both run on the same machine, and there is only one single OrientDB instance.

Expected behavior

Return the size of the database

Actual behavior

Sometimes it return the db size, but sometimes there is:

 Error executing request
java.util.ConcurrentModificationException
  at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:901)
  at java.util.ArrayList$Itr.next(ArrayList.java:851)
  at com.orientechnologies.orient.core.storage.impl.local.OAbstractPaginatedStorage.getSize(OAbstractPaginatedStorage.java:2347)
  at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.sizeDatabase(ONetworkProtocolBinary.java:1069)
  at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.executeRequest(ONetworkProtocolBinary.java:373)
  at com.orientechnologies.orient.server.network.protocol.binary.ONetworkProtocolBinary.execute(ONetworkProtocolBinary.java:199)
  at com.orientechnologies.common.thread.OSoftThread.run(OSoftThread.java:77)

Steps to reproduce

What my app does is upserting +20k items in the database (using the rest api) while regularly asking for the db size at the same time, in parallel. Sometimes it works, sometimes there is this exception.

Is that allowed/possible? or is there another way?

[lvca]

Fixed in 2.2.x branch. it will be part of the next 2.2.17, but you can already use a build from the branch 2.2.x. Thanks.

[jbilcke]

woa! thank you! :)