Hello,

> I'm currently developing a map/reduce program that emits a fair amount
> of maps per input record (around 50 - 100), and I'm getting OutOfMemory
> errors:

Sorry for the noise, I found out I had to set the mapred.child.java.opts 
JobConf parameter to "-Xmx512m" to make 512MB of heap space available in the 
map processes.

However, I was wondering: are these hard architectural limits? Say that I 
wanted to emit 25,000 maps for a single input record, would that mean that I 
will require huge amounts of (virtual) memory? In other words, what exactly is 
the reason that increasing the number of emitted maps per input record causes 
an OutOfMemoryError ?

Regards,

Leon Mergen

Reply via email to