I have written a standalone java program that fetches records from the database and calculates the checksum of each table.
The problem I am facing is with tables containing huge data sets, my program resutls in an Out of Memory error.
Below is the error that I get when I run the program with following options :
java -Xms256m -Xmx1536m DatabaseCheck.DBCheckSum
JVMDG303: JVM Requesting Java core file
JVMDG304: Java core file written to /opt/projects/gsd/java/DatabaseCheck/javacore430152.1231233966.txt
JVMDG274: Dump Handler has Processed OutOfMemory.
JVMST109: Insufficient space in Javaheap to satisfy allocation request
Exception in thread "main" java.lang.OutOfMemoryError
I have tried using setFetchSize(Integer.MIN) method to limit the number of records retrieved but this approach also does not work.
Below is sample code of my program:
If anybody can help me with this then it will be great!
posted 7 years ago
You know, each byte of a byte allocates exactly one byte of memory?
Can you now imagine what will happen if the byte contains more bytes than the JVM available memory?
Either give it more memory or buffer the bytes in an InputStream.