Frequently Asked Questions

1. Q: I get a "java.lang.OutOfMemory" error when trying to sort/open a file. What's wrong?
   A: JVM (Java Virtual Machine) can use only 64MB of memory by default. You can increase the amount by adding a switch -Xmx###M to the grain.sh/grain.bat script. Here ### stands for the amount you want java to use in megabytes, value should not exceed the amount of physical memory or 512.

2. Q: I get a "java.lang.ClassNotFoundException:" (followed by my sort class) when I try to sort. Why the sorter does not find it?
   A: The dynamic class loader only loads classes from the directory where the grain_beta.jar library is.

3. Q: Grain produces .aida files. How can I view them?
   A: You can load them into Grain by using "File->Open". Aida is a standardiced format so you can try also e.g. JAS3.

4. Q: Which tape devices should I use when sorting from tape?
   A: Use /dev/nst? in Linux and /dev/rmt/?hbn in Solaris.

5. Q: Why I can't read tapes written in Jyvaskyla with my DLT7000 drive?
   A: Most probably the tapes have been written in a DLT8000 drive with the highest density which the DLT7000 drives don't support. You must either write the tapes originally with the 70/35MB density override or copy them from a DLT8000 drive to DLT7000 drive hoping they are not too large or buy a DLT8000 drive or ...