In most cases it is not necessary to specify any additional arguments to the Java runtime, but it can be useful in certain circumstances. The two main kinds of options you might want to specify directly to Java are these:
-Dname=value
.
So for instance to ensure that temporary files are written to
the /home/scratch
directory, you could use the flag
-Djava.io.tmpdir=/home/scratch
OutOfMemoryError
then this has
proved too small for the job in hand. You can increase the
heap memory with the -Xmx
flag. To set the heap
memory size to 256 megabytes, use the flag
-Xmx256M(don't forget the 'M' for megabyte). You will probably find performance is poor if you specify a heap size larger than the physical memory of the machine you're running on.
Note however that encouraging STILTS to use disk files
rather than memory for temporary storage is often a
better idea than boosting the heap memory -
this is done by specifying the -disk
flag on most of the
tools, or possibly -Dstartable.storage=disk
.
You can specify other options to Java such as tuning and profiling flags etc, but if you want to do that sort of thing you probably don't need me to tell you about it.