In top command output I see aio/0,ato/0,events/0,kacpid,kblocked/0,pdflush,scsi_eh_o,migration/0 without any command evoked. What are all these command or process

resoponcible?

[ah] Nothing to worry about Komal. These are kernel mode processes that are required for marinating states of devices and file-systems. Ideally they shouldn't take much juice from the CPU :).

[ah] Regards,

ah