Page History

On this page

Cassandra fails with the "java.lang.OutOfMemoryError: Direct buffer memory" error

With some large databases, Cassandra may fail with the following error:

java.lang.OutOfMemoryError: Direct buffer memory
 at java.nio.Bits.reserveMemory(Bits.java:694)
 at java.nio.DirectByteBuffer.<init>(DirectByteBuffer.java:123)
 at java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:311)
 at org.apache.cassandra.utils.memory.BufferPool.allocate(BufferPool.java:110)
 at org.apache.cassandra.utils.memory.BufferPool.access$1000(BufferPool.java:46)
 at org.apache.cassandra.utils.memory.BufferPool$LocalPool.allocate(BufferPool.java:407)
 at org.apache.cassandra.utils.memory.BufferPool$LocalPool.access$000(BufferPool.java:334)
 at org.apache.cassandra.utils.memory.BufferPool.takeFromPool(BufferPool.java:122)
 at org.apache.cassandra.utils.memory.BufferPool.get(BufferPool.java:94)
 at org.apache.cassandra.cache.ChunkCache.load(ChunkCache.java:155)
 at org.apache.cassandra.cache.ChunkCache.load(ChunkCache.java:39)

To solve the problem do one of the following

• Increase the memory (Xmx VM option) for Cassandra until the migration is successful.
• Set "file_cache_size_in_mb: 0" In the cassandra.yaml file to disable the chunk cache completely.

"All commit element IDs" index is corrupted

If the "all commit element IDs" index is corrupted, migration may fail and print and error of the following format into the Migrator's log file:

It has been detected that "all commit element IDs" index is corrupted at revision <revision> of resource <resource.id>

To solve the problem

1. Wait until all selected projects finish migrating.
2. Stop the Migrator (backend) process.
3. At the end of the migrator's application.conf file, add the following line:
   esi.migration.source-revision-all-object-ids-getter.prefer-bfs=true
4. Start the Migrator and retry the migration of the failed project from the Migrator GUI.

With this setting in place, it is expected that the migration progress will be much slower so it is recommended to finish the affected project with this setting and then revert back.

The "java.net.SocketException: Too many open files" error appears during migration

This error usually means that the Cassandra or Teamwork Cloud process is running into system-imposed limits on a number of open files.

To solve the problem

1. Set the following limits in /etc/security/limits.conf.
   localUser hard nofile 50000
   localUser hard nproc 50000
   localUser soft nofile 40000
   localUser soft nproc 40000
   cassandra hard nofile 50000
   cassandra hard nproc 50000
   cassandra soft nofile 40000
   cassandra soft nproc 40000
   root hard nofile 50000
   root hard nproc 50000
   root soft nofile 40000
   root soft nproc 40000
2. Restart the processes.

Limits are configurable to separate users (like the Cassandra user that runs Cassandra or the Teamwork Cloud user that runs the Teamwork Cloud service). For more information, see https://linux.die.net/man/5/limits.conf.

The "com.datastax.driver.core.exceptions.AuthenticationException" exception is shown in the log file

If the The following exception is shown in the log file:

Error while trying to activate [com.nomagic.esi.server.core.a.d.c, main]
com.datastax.driver.core.exceptions.AuthenticationException: Authentication error on host FQDN/IP: Provided username cassandra and/or password are incorrect

To solve the problem

• Add the following configuration block to application.conf of the migrator artefact:

  Code Block
  authentication-enabled = true authentication { username = your_cassandra_username password = your_cassandra_password }