Re: Determining Running Applications on Specific CPU

["Archimedes Gaviola" <archimedes.gaviola@xxxxxxxxx>]

On Wed, Aug 20, 2008 at 12:28 PM, Dylan Reinhold <dylan@ocnetworking.com> wrote:
> This is the top output from a MP Box
>
> load averages:  2.29,  1.02,  0.41                      up 0+00:05:03
>  21:33:47
> 39 processes:  39 running
> CPU0 states: 16.2% user,  0.0% nice, 53.0% system, 21.1% interrupt,  9.7%
> idle
> CPU1 states: 39.5% user,  0.0% nice, 23.5% system, 27.1% interrupt, 10.0%
> idle
> Mem: 13M Active, 81M Inact, 79M Wired, 20K Cache, 60M Buf, 322M Free
> Swap: 1024M Total, 1024M Free
>
>
>
> Hope this helps
>
> Dylan
>

First of, thanks to all of you who share your thoughts with my
concern. Basically, this concern arises based on my use with
FreeBSD-6.2 on an AMD-64 IBM machine with 4 dual-core CPUs. What I've
found out is that whenever I run my application (my_app), a
CPU-intensive application, each CPU is randomly selected to process
this application. See below with the top command while looking at the
'C' column for the processor processing my_app application.

root@fbsd62-PH# top -S
last pid: 13336;  load averages:  1.03,  1.05,  1.01
     up 1+01:38:04  09:12:40
133 processes: 10 running, 107 sleeping, 16 waiting
CPU states:  0.3% user,  0.0% nice, 17.4% system,  0.0% interrupt, 82.3% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
13280 root        1 102    0 13156K  4016K CPU2   2   1:29 99.35% my_app
   17 root        1 171   52     0K    16K RUN    0  21.3H 97.95% idle: cpu0
   14 root        1 171   52     0K    16K CPU3   3  22.4H 89.94% idle: cpu3
   15 root        1 171   52     0K    16K RUN    2  20.1H 85.64% idle: cpu2
   10 root        1 171   52     0K    16K CPU7   7  20.5H 81.05% idle: cpu7
   11 root        1 171   52     0K    16K CPU6   6  20.3H 79.30% idle: cpu6
   13 root        1 171   52     0K    16K CPU4   4  20.0H 78.52% idle: cpu4
   12 root        1 171   52     0K    16K CPU5   5  21.2H 75.73% idle: cpu5
   16 root        1 171   52     0K    16K CPU1   1  18.0H 60.01% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13338;  load averages:  1.03,  1.05,  1.01
     up 1+01:38:10  09:12:46
133 processes: 10 running, 107 sleeping, 16 waiting
CPU states:  0.1% user,  0.0% nice, 17.7% system,  0.0% interrupt, 82.2% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
13280 root        1 102    0 13156K  3772K CPU2   3   1:35 99.29% my_app
   17 root        1 171   52     0K    16K CPU0   0  21.3H 98.00% idle: cpu0
   14 root        1 171   52     0K    16K CPU3   3  22.4H 90.58% idle: cpu3
   15 root        1 171   52     0K    16K RUN    2  20.1H 84.67% idle: cpu2
   10 root        1 171   52     0K    16K CPU7   7  20.5H 80.03% idle: cpu7
   11 root        1 171   52     0K    16K RUN    6  20.3H 78.37% idle: cpu6
   13 root        1 171   52     0K    16K CPU4   4  20.0H 77.59% idle: cpu4
   12 root        1 171   52     0K    16K CPU5   5  21.2H 76.22% idle: cpu5
   16 root        1 171   52     0K    16K CPU1   1  18.0H 63.23% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13341;  load averages:  1.02,  1.05,  1.01
     up 1+01:38:18  09:12:54
133 processes: 11 running, 107 sleeping, 15 waiting
CPU states:  0.3% user,  0.0% nice, 17.3% system,  0.0% interrupt, 82.4% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
13280 root        1 101    0 13156K  3988K CPU4   0   1:43 99.25% my_app
   17 root        1 171   52     0K    16K RUN    0  21.3H 97.90% idle: cpu0
   14 root        1 171   52     0K    16K CPU3   3  22.4H 89.99% idle: cpu3
   15 root        1 171   52     0K    16K CPU2   2  20.1H 85.45% idle: cpu2
   10 root        1 171   52     0K    16K RUN    7  20.5H 80.42% idle: cpu7
   11 root        1 171   52     0K    16K CPU6   6  20.3H 78.76% idle: cpu6
   13 root        1 171   52     0K    16K RUN    4  20.0H 75.93% idle: cpu4
   12 root        1 171   52     0K    16K CPU5   5  21.2H 75.44% idle: cpu5
   16 root        1 171   52     0K    16K CPU1   1  18.0H 64.11% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13343;  load averages:  1.02,  1.05,  1.01
     up 1+01:38:25  09:13:01
133 processes: 12 running, 105 sleeping, 16 waiting
CPU states:  0.4% user,  0.0% nice, 16.6% system,  0.0% interrupt, 83.0% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
13280 root        1 100    0 13156K  4032K CPU7   0   1:50 99.28% my_app
   17 root        1 171   52     0K    16K CPU0   0  21.3H 98.05% idle: cpu0
   14 root        1 171   52     0K    16K CPU3   3  22.4H 90.58% idle: cpu3
   15 root        1 171   52     0K    16K RUN    2  20.1H 85.25% idle: cpu2
   10 root        1 171   52     0K    16K RUN    7  20.5H 80.22% idle: cpu7
   11 root        1 171   52     0K    16K RUN    6  20.3H 78.56% idle: cpu6
   13 root        1 171   52     0K    16K RUN    4  20.0H 77.29% idle: cpu4
   12 root        1 171   52     0K    16K RUN    5  21.2H 75.73% idle: cpu5
   16 root        1 171   52     0K    16K CPU1   1  18.0H 62.30% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13345;  load averages:  1.02,  1.05,  1.01
     up 1+01:38:32  09:13:08
133 processes: 10 running, 107 sleeping, 15 waiting, 1 lock
CPU states:  0.4% user,  0.0% nice, 17.4% system,  0.1% interrupt, 82.1% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
13280 root        1 100    0 13156K  3944K CPU7   0   1:57 99.31% my_app
   17 root        1 171   52     0K    16K RUN    0  21.3H 98.05% idle: cpu0
   14 root        1 171   52     0K    16K CPU3   3  22.4H 89.36% idle: cpu3
   15 root        1 171   52     0K    16K CPU2   2  20.1H 85.55% idle: cpu2
   10 root        1 171   52     0K    16K RUN    7  20.5H 81.69% idle: cpu7
   11 root        1 171   52     0K    16K CPU6   6  20.3H 78.42% idle: cpu6
   13 root        1 171   52     0K    16K CPU4   4  20.0H 76.51% idle: cpu4
   12 root        1 171   52     0K    16K CPU5   5  21.2H 74.76% idle: cpu5
   16 root        1 171   52     0K    16K CPU1   1  18.0H 64.06% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13384;  load averages:  1.01,  1.04,  1.01
     up 1+01:38:51  09:13:27
133 processes: 10 running, 107 sleeping, 16 waiting
CPU states:  0.5% user,  0.0% nice, 17.8% system,  0.1% interrupt, 81.6% idle
Mem: 49M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
   17 root        1 171   52     0K    16K CPU0   0  21.3H 97.95% idle: cpu0
13382 root        1 100    0 13092K  3644K CPU4   2   0:12 94.01% my_app
   14 root        1 171   52     0K    16K CPU3   3  22.4H 88.92% idle: cpu3
   15 root        1 171   52     0K    16K CPU2   2  20.1H 83.74% idle: cpu2
   10 root        1 171   52     0K    16K RUN    7  20.5H 79.20% idle: cpu7
   11 root        1 171   52     0K    16K CPU6   6  20.3H 78.91% idle: cpu6
   12 root        1 171   52     0K    16K CPU5   5  21.2H 76.90% idle: cpu5
   13 root        1 171   52     0K    16K RUN    4  20.0H 76.27% idle: cpu4
   16 root        1 171   52     0K    16K CPU1   1  18.0H 65.92% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13391;  load averages:  1.01,  1.04,  1.01
    up 1+01:39:04  09:13:40
133 processes: 10 running, 107 sleeping, 16 waiting
CPU states:  0.7% user,  0.0% nice, 15.6% system,  0.0% interrupt, 83.8% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
   17 root        1 171   52     0K    16K CPU0   0  21.3H 98.00% idle: cpu0
13382 root        1 101    0 13092K  3912K CPU1   1   0:26 97.60% my_app
   14 root        1 171   52     0K    16K CPU3   3  22.4H 90.72% idle: cpu3
   15 root        1 171   52     0K    16K CPU2   2  20.1H 88.96% idle: cpu2
   11 root        1 171   52     0K    16K RUN    6  20.3H 81.64% idle: cpu6
   12 root        1 171   52     0K    16K CPU5   5  21.2H 79.05% idle: cpu5
   10 root        1 171   52     0K    16K CPU7   7  20.5H 78.08% idle: cpu7
   13 root        1 171   52     0K    16K CPU4   4  20.0H 72.61% idle: cpu4
   16 root        1 171   52     0K    16K RUN    1  18.0H 59.77% idle: cpu1

root@fbsd62-PH# top -S
last pid: 13441;  load averages:  1.04,  1.04,  1.01
     up 1+01:40:07  09:14:43
133 processes: 10 running, 107 sleeping, 16 waiting
CPU states:  0.6% user,  0.1% nice, 18.4% system,  0.0% interrupt, 81.0% idle
Mem: 50M Active, 20M Inact, 69M Wired, 23M Buf, 27G Free
Swap:

  PID USERNAME  THR PRI NICE   SIZE    RES STATE  C   TIME   WCPU COMMAND
13382 root        1 101    0 13156K  4024K CPU1   5   1:28 99.30% my_app
   17 root        1 171   52     0K    16K CPU0   0  21.3H 98.10% idle: cpu0
   14 root        1 171   52     0K    16K CPU3   3  22.4H 91.50% idle: cpu3
   10 root        1 171   52     0K    16K RUN    7  20.5H 89.60% idle: cpu7
   15 root        1 171   52     0K    16K CPU2   2  20.1H 84.81% idle: cpu2
   11 root        1 171   52     0K    16K CPU6   6  20.3H 82.62% idle: cpu6
   12 root        1 171   52     0K    16K CPU5   5  21.3H 77.64% idle: cpu5
   13 root        1 171   52     0K    16K CPU4   4  20.0H 73.97% idle: cpu4
   16 root        1 171   52     0K    16K RUN    1  18.0H 53.32% idle: cpu1

Here, I'm only showing one running application but the same thing
happen when 2 or 3 another applications are running, it still be
randomly processed by CPUs. Suppose to be I want to test DragonFly on
this machine but unfortunately AMD-64 is still an ongoing development
as of this time. I wanted to test to be able to know how DragonFly
behaves on an MP-based system since it contains LWKT scheduler per
CPU.

Thanks,
Archimedes