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Code Block
java -Xmx1g -jar duracloudsync-{version}.jar

Alternatively, you can set the system environment variable JAVA_TOOL_OPTIONS to a value like "-Xmx1g", which will be picked up by the SyncTool on startup, meaning that you can start up the SyncTool UI as usual.

To run the SyncTool in command-line mode with 1 GB of heap memory space, download the Jar version of the SyncTool and execute the above command followed by the command line parameter values.

Large Files

When the SyncTool encounters a large file (by default, this is 1 GB+, but this can be set up to 5GB via the --max-file-size parameter) it will "chunk" that file prior to transfer to DuraCloud. This means that the file will land in DuraCloud as multiple components with an associated manifest file to indicate the set of component files and the checksum of each. As part of this process, the SyncTool will create a local temporary file for each chunk prior to transfer, as this allows the tool to generate the checksum for that chunk, and also allows retries on failure. These temporary files are stored in the default java temp directory.

The number and size of temp files which may be created depends on the number of threads and the max chunk size settings. Each thread has the potential of creating one temp file at a time and the size of the temp files can be up to the max chunk size. So multiplying the number of threads setting by the max chunk size will tell you the maximum number of GBs that may be consumed on local storage at one time. The SyncTool removes temp files as transfers complete, but if the tool it terminated abruptly, some of those temp files can be orphaned (and may require manual cleanup.)

If you'd like to change the location of where temp files are stored, this can be done with the "" system property. This can be done on the command line, by adding  "" after "java" on the command line. Alternatively, you can set the system environment variable JAVA_TOOL_OPTIONS to this value ("") and it will be picked up as the tool starts.



As of DuraCloud version 4.0.0, the Sync Tool requires Java 8 to run. The latest version of Java can be downloaded from here.