Multiple SQLPLUS background processes not working properly

Shell Programming and Scripting
1

Hi All,
I am running 25 background process from a Unix shell script which calls a single Oracle procedure with different paramenters each time.
These 25 process creates 25 different files.
When i run these 25 Background SQLPLUS processes, few files are not created completly but if i run 25 processes one-by-one then all 25 files are created properly with data.

My Doubt is :
1) Is there any restriction on number of SQLPLUS Background processes to run from script?
2) Are they affected by file size as size of files is in around 45K Bytes?

For info i am not using any Global temporary table for creating files.

Thanks

2

Do you make each call with a

nohup command & 
..............
..............
wait

limits to the number of child processes - see

getconf _SC_CHILD_MAX  
# some systems getconf CHILD_MAX

for your system.