Kernel threads and system usage metric.

Doubt! The processes that appear in top with brackets are the kernel threads? If so, this threads spend all its time on system mode, right? By the system mode I mean the %sy on top header, since kernel threads hasn't any memory mapped to user space, it can't run on user space at any time, right? So the total of system mode usage is the sum of all processes processing in kernel space, plus the kernel threads processing, right? Thanks in advance! -- Follow the white rabbit!