On Saturday 17 February 2007, Alex Schuster wrote: > > Shouldn't top have provided some kind of info for why the CPU usage > > was 100% for 5 minutes straight? If it does display trends, > > shouldn't it have picked up on that one? > > I bet it was updatedb. This is what top shows me when it is running:
or eupdatedb, or prelink... :-) > Cpu(s): 15.6% us, 12.6% sy, 0.3% ni, 0.0% id, 70.2% wa, 1.3% hi, > 0.0% si PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ > COMMAND 1563 root 18 0 1936 928 528 R 8.9 0.2 0:09.68 > updatedb > > Whatever this "wa" entry is, probably something with I/O related > waiting, it seems is it not being taken into account for the %CPU > culumn entry of the process. "wa" is "wait" - a process is trying to do IO and it is being blocked as something else is using a resource the process wants to use. SO it sits and does nothing, much the same way you sometimes sit in your car and do nothing at the McDonalds drive-through queue. Usually a blocked process will consume no cpu time (as it's doing nothing), but it can slow the machine down and make it less responsive while many processes sit and wait alan -- Optimists say the glass is half full, Pessimists say the glass is half empty, Developers say wtf is the glass twice as big as it needs to be? Alan McKinnon alan at linuxholdings dot co dot za +27 82, double three seven, one nine three five -- [email protected] mailing list
