update/delete records concurrently without impact to other process for handling huge data? I tried to googling first, but i didn't get it . . .

So, What are best practices for update/delete records concurrently without impact to other process handle to huge data(>5 millions records)?

Please point to me.

Thanks you.
If you can apply partitioning to the table(s) in question you can swap out whole partitions then drop the swapped partitions.  This is extremely fast and resource-light.

It requires minimum versions and editions, however, and your question's tags don't specify this.  It also imposes some prerequesites on your tables' keys.