I used LOAD utility to load data into a tablespace with 1 container on LVM with 2 physical disks, DB2_PARALLEL_IO is also set to 2. it took about 22 mins.
repeated the same test case with tablespace with 1 container on LVM with 1 physical disk. it takes the same 22 mins.
Parallel writing is happening for sure when I observe iostat output on physical devices [/dev/sdb1,sdd1].but getting same speed of writing around 900kbps. Each physical device is capable of 1Mbps. So was expecting parallel writing of containers should improve write times. but seems not.
Please be aware of all these things are happening in a VM.