i mining now v2pool when my miner run i generating plot with gpu ploter 2.1.1 at the same but i get this error sometimes.
whtas yours idea?

Java needs more memory.... It wants all your memory!!
i have 8gig ram in my pc now 78% my ram in use.
Because this for i mining with generate plot at the same time or not?
edit the .bat file you start mining with it should look something like this:
"C:\Program Files\Java\jre7\bin\java.exe" -Xmx1024m -cp pocminer.jar;lib/*;lib/akka/*;lib/jetty/* pocminer.POCMiner
increase the -Xmx number.. I use 1024 with no errors.. if that dont fix it then it is something else that I do not know
i use pocminer_pool_v1 in my bat file not Xmx.
this is my bat file conf in miner folder.
java -cp pocminer_pool.jar;lib/*;lib/akka/*;lib/jetty/* pocminer_pool.POCMiner mine
http://127.0.0.1:8125 http://178.62.39.204:8121