Again in another server i gave 16GB as heap size, here also this problem "Failed to connect to ::1: Cannot assign requested address" is coming. May be you are right, bulk is the procedure i should go for.
But in between please check what is the cause for it to happen.
I am testing in one server cluster(just for testing). It has 32 processor cores and 132 GB RAM. I gave 16 GB as heap space. If you can point me in the right direction, then it will be great use.