Re: "busy" load counters

From: Albert Cahalan (albert_at_users.sf.net)
Date: 09/13/03

  • Next message: Vojtech Pavlik: "Re: [PATCH] ioctl entries for joystick in compat_ioctl.h" 
    To: linux-kernel mailing list <linux-kernel@vger.kernel.org>
Date:	13 Sep 2003 03:00:51 -0400

    Xuân Baldauf writes:

    > Currently, tools like "top" show stats like
    >
    > Cpu(s): 92.1% user, 6.9% system, 0.0% nice, 1.0% idle
    >
    > Unfortunately, these stats are not sufficient to determine wether the
    > system is "busy". Determining wether the system is "busy" is very useful
    > in case an interactive application (e.g. a shell or some shell command)
    > does not respond.
    > Maybe it just hangs (waits for input) or does serious work (e.g. uses
    > the CPU or accesses the disk). Disk access is not visible in "top".
    > Depending on the machine, on disk accesses, there might be a slight or
    > significant rise in the "system" portion of those stats, but this is not
    > trustable.

    The feature is available, but you'll need to upgrade
    to procps-3.1.12 and linux-2.6.0-test4 at least.

    http://www.kernel.org/pub/linux/kernel/v2.6/
    http://procps.sf.net/

    Once you've done that, both "top" and "vmstat" will
    supply the info you want. There are 7 basic %CPU stats
    right now:

    us regular user apps
    sy system (general kernel stuff)
    ni nice user apps (low-priority tasks)
    id idle
    wa waiting for IO to complete
    hi hard interrupt (IRQ) handlers
    si soft interrupt (network stack, mostly?) handlers

    The "top" program shows all of those. The "vmstat"
    program mixes "ni" into "us", and mixes "hi" and "si"
    into "sy". An example for each:

    procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
     r b swpd free buff cache si so bi bo in cs us sy id wa
     0 0 0 6896 2668 108896 0 0 0 1 34 14 10 3 87 0

    top - 02:56:17 up 12 days, 13:43, 25 users, load average: 0.37, 0.25, 0.22
    Tasks: 129 total, 4 running, 124 sleeping, 1 stopped, 0 zombie
    Cpu(s): 8.6% us, 5.6% sy, 0.0% ni, 85.8% id, 0.0% wa, 0.0% hi, 0.0% si
    Mem: 513924k total, 507068k used, 6856k free, 2664k buffers
    Swap: 0k total, 0k used, 0k free, 108844k cached

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

  • Next message: Vojtech Pavlik: "Re: [PATCH] ioctl entries for joystick in compat_ioctl.h"

    Relevant Pages

    • Re: [Lhms-devel] [PATCH 0/7] Fragmentation Avoidance V19
      ... ia64 SN2 system, with a single thread, or about 20 times a second ... If more folks need these detailed stats, then that's how it should be. ... more detail than the sorts of stats you are suggesting. ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • Re: [patch] swapin rlimit
      ... generic problem with /proc based stats. ... and stats updates would have to update this page ... Another addition would be some mechanism for a monitoring app to capture ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • Re: reiser4 plugins
      ... >handles recognition and invocation of application bundles (and there ... >is an 'open' shell command that does the same thing). ... Note that MacOS has the monopoly on what they ship, ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • Re: Hard freeze with 2.6.10-rc3 and QoS, worked fine with 2.6.9
      ... This seems to point to probably be a backward compat issue which was ... overlooked in the stats. ... > input device check on ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)
    • [PATCH 3/5] slab: extract slabinfo header printing to separate function
      ... #ifdef CONFIG_PROC_FS ... #if STATS ... send the line "unsubscribe linux-kernel" in ...
      (Linux-Kernel)