On Sat, Jun 07, 2003 at 03:17:15PM -0400, Jeff Bollinger wrote: > Hello all, quick question about a RedHat 7.2 system (2.4.20-13.7 Kernel). > I tried searching Redhat.com, Google, the TriLUG archives, as well as the > man pages and `apropos`, but could not find any information about a > process that I have running called "kscand". Can anyone explain what this > is/does?
Red Hat has been using Rik van Riel's vm overhaul (around the time he was still working for Conectiva) known as "rmap." There's more informa- tion here: http://lwn.net/2002/0124/kernel.php3 (and generally, if you're interested in kernel hacking, check out the #kernelnewbies channel on OFTC). As a side note, vanilla 2.4 (as well as SuSE's kernel) doesn't have this daemon because rmap isn't integrated. 2.5 does have it, though I don't remember if the name has stuck around. In a nutshell, the "kscand" you see is reported by `ps' as another process despite it being a kernel thread spawned by the `init' process. (This has to do with the ways both Linux creates/treats threads and how they're reported to userspace applications.) It's quite important to the function of your system, so don't be alarmed. Essentially it runs in the background as a low-priority thread and tracks what pages in virtual memory have been most to least active, so it basically keeps a running tally of their "ages." This is tightly-integrated into the vm system because it helps determine what applications can continue to use physical RAM (versus being paged out, ala to swap). > While I'm asking, what do processes contained in square brackets mean > also? Some processes appear in these brackets when I run `ps`. They're kernel threads spawned by the `init' process and invoked in arch/$ARCH/kernel/process.c::kernel_thread() . -- Dan Chen [EMAIL PROTECTED] GPG key: www.unc.edu/~crimsun/pubkey.gpg.asc _______________________________________________ TriLUG mailing list http://www.trilug.org/mailman/listinfo/trilug TriLUG Organizational FAQ: http://www.trilug.org/faq/TriLUG-faq.html
