high %CPU values after upgrading to the last stable kernel

high %CPU values after upgrading to the last stable kernel

[sbs]

after upgrading from 2.6.16 to 2.6.27 kernel top shows a strange
picture of extremely highly %CPU values.

# top -V
        top: procps version 3.2.6


# top
top - 04:24:06 up 7 days,  1:12,  1 user,  load average: 2.28, 2.03, 2.00
Tasks: 183 total,   2 running, 181 sleeping,   0 stopped,   0 zombie
Cpu(s): 36.2% us,  2.4% sy,  0.0% ni, 56.1% id,  4.7% wa,  0.1% hi,  0.5% si
Mem:  12473092k total, 11169060k used,  1304032k free,       16k buffers
Swap:  2048248k total,      636k used,  2047612k free,  1257988k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
19824 b      20   0 92212  17m 5420 S 4308  0.1   1:39.49 httpd
14396 b      20   0 92716  28m  16m S 3721  0.2  38:47.38 httpd
14024 b      20   0 92376  28m  16m S 2437  0.2  51:49.68 httpd
 7415 b      20   0 96876  40m  24m D 2146  0.3  93:59.72 httpd
 8182 b      20   0 94500  36m  21m S 1997  0.3 111:41.60 httpd
13461 b      20   0 94240  31m  17m S 1439  0.3  48:43.71 httpd
 8466 b      20   0 92036  32m  21m S 1136  0.3 107:37.90 httpd
17620 b      20   0 92660  23m  11m S 1003  0.2  10:55.03 httpd
14025 b      20   0 92000  28m  16m S  720  0.2  51:49.49 httpd
 3808 nobody    20   0 3013m 2.9g  592 S  714 24.7 343030:50 memcached
   10 root     15  -5     0    0    0 S  714  0.0  11881:28 ksoftirqd/3
18487 b      20   0 91416  20m 9572 S  580  0.2   8:29.20 httpd
13252 b      20   0 93408  30m  17m S  580  0.3  45:19.69 httpd
17525 b      20   0 93208  23m  10m S  566  0.2  18:34.40 httpd
14760 b      20   0 93452  28m  15m S  534  0.2  57:34.65 httpd
 3804 nobody    20   0 2995m 2.9g  592 S  441 24.6 378908:26 memcached
12209 b      20   0 92312  28m  16m S  279  0.2  63:28.45 httpd



%CPU is 4308 here and it's not the highest value.
i havent seen that on any previous kernel on the same server.

should i upgrade procps or downgrade kernel then to get proper values back? :)
or is it a feature of the new kernel?

thank you

Re: high %CPU values after upgrading to the last stable kernel

[Frédéric Weisbecker]

2008/10/22 sbs <gexlie@gmail.com>:
> after upgrading from 2.6.16 to 2.6.27 kernel top shows a strange
> picture of extremely highly %CPU values.
>
> # top -V
>        top: procps version 3.2.6
>
>
> # top
> top - 04:24:06 up 7 days,  1:12,  1 user,  load average: 2.28, 2.03, 2.00
> Tasks: 183 total,   2 running, 181 sleeping,   0 stopped,   0 zombie
> Cpu(s): 36.2% us,  2.4% sy,  0.0% ni, 56.1% id,  4.7% wa,  0.1% hi,  0.5% si
> Mem:  12473092k total, 11169060k used,  1304032k free,       16k buffers
> Swap:  2048248k total,      636k used,  2047612k free,  1257988k cached
>
>  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
> 19824 b      20   0 92212  17m 5420 S 4308  0.1   1:39.49 httpd
> 14396 b      20   0 92716  28m  16m S 3721  0.2  38:47.38 httpd
> 14024 b      20   0 92376  28m  16m S 2437  0.2  51:49.68 httpd
>  7415 b      20   0 96876  40m  24m D 2146  0.3  93:59.72 httpd
>  8182 b      20   0 94500  36m  21m S 1997  0.3 111:41.60 httpd
> 13461 b      20   0 94240  31m  17m S 1439  0.3  48:43.71 httpd
>  8466 b      20   0 92036  32m  21m S 1136  0.3 107:37.90 httpd
> 17620 b      20   0 92660  23m  11m S 1003  0.2  10:55.03 httpd
> 14025 b      20   0 92000  28m  16m S  720  0.2  51:49.49 httpd
>  3808 nobody    20   0 3013m 2.9g  592 S  714 24.7 343030:50 memcached
>   10 root     15  -5     0    0    0 S  714  0.0  11881:28 ksoftirqd/3
> 18487 b      20   0 91416  20m 9572 S  580  0.2   8:29.20 httpd
> 13252 b      20   0 93408  30m  17m S  580  0.3  45:19.69 httpd
> 17525 b      20   0 93208  23m  10m S  566  0.2  18:34.40 httpd
> 14760 b      20   0 93452  28m  15m S  534  0.2  57:34.65 httpd
>  3804 nobody    20   0 2995m 2.9g  592 S  441 24.6 378908:26 memcached
> 12209 b      20   0 92312  28m  16m S  279  0.2  63:28.45 httpd
>
>
>
> %CPU is 4308 here and it's not the highest value.
> i havent seen that on any previous kernel on the same server.
>
> should i upgrade procps or downgrade kernel then to get proper values back? :)
> or is it a feature of the new kernel?
>
> thank you
> --
> 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/
>

Hi,

It really depends on what your box is doing at the time you capture
the cpu usage.
And it really depends too of your kernel config...

Re: high %CPU values after upgrading to the last stable kernel

[Ray Lee]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=UTF-8, Size: 2798 bytes --]

On Wed, Oct 22, 2008 at 2:04 PM, Frédéric Weisbecker <fweisbec@gmail.com> wrote:> 2008/10/22 sbs <gexlie@gmail.com>:>> after upgrading from 2.6.16 to 2.6.27 kernel top shows a strange>> picture of extremely highly %CPU values.>>>> # top -V>>        top: procps version 3.2.6>>>>>> # top>> top - 04:24:06 up 7 days,  1:12,  1 user,  load average: 2.28, 2.03, 2.00>> Tasks: 183 total,   2 running, 181 sleeping,   0 stopped,   0 zombie>> Cpu(s): 36.2% us,  2.4% sy,  0.0% ni, 56.1% id,  4.7% wa,  0.1% hi,  0.5% si>> Mem:  12473092k total, 11169060k used,  1304032k free,       16k buffers>> Swap:  2048248k total,      636k used,  2047612k free,  1257988k cached>>>>  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND>> 19824 b      20   0 92212  17m 5420 S 4308  0.1   1:39.49 httpd>> 14396 b      20   0 92716  28m  16m S 3721  0.2  38:47.38 httpd>> 14024 b      20   0 92376  28m  16m S 2437  0.2  51:49.68 httpd>>  7415 b      20   0 96876  40m  24m D 2146  0.3  93:59.72 httpd>>  8182 b      20   0 94500  36m  21m S 1997  0.3 111:41.60 httpd>> 13461 b      20   0 94240  31m  17m S 1439  0.3  48:43.71 httpd>>  8466 b      20   0 92036  32m  21m S 1136  0.3 107:37.90 httpd>> 17620 b      20   0 92660  23m  11m S 1003  0.2  10:55.03 httpd>> 14025 b      20   0 92000  28m  16m S  720  0.2  51:49.49 httpd>>  3808 nobody    20   0 3013m 2.9g  592 S  714 24.7 343030:50 memcached>>   10 root     15  -5     0    0    0 S  714  0.0  11881:28 ksoftirqd/3>> 18487 b      20   0 91416  20m 9572 S  580  0.2   8:29.20 httpd>> 13252 b      20   0 93408  30m  17m S  580  0.3  45:19.69 httpd>> 17525 b      20   0 93208  23m  10m S  566  0.2  18:34.40 httpd>> 14760 b      20   0 93452  28m  15m S  534  0.2  57:34.65 httpd>>  3804 nobody    20   0 2995m 2.9g  592 S  441 24.6 378908:26 memcached>> 12209 b      20   0 92312  28m  16m S  279  0.2  63:28.45 httpd>>>>>>>> %CPU is 4308 here and it's not the highest value.>> i havent seen that on any previous kernel on the same server.>>>> should i upgrade procps or downgrade kernel then to get proper values back? :)>> or is it a feature of the new kernel?>>>> thank you>>>> Hi,>> It really depends on what your box is doing at the time you capture> the cpu usage.> And it really depends too of your kernel config...
It really shouldn't, we're talking about /proc which is supposed to bea stable userspace interface.
Try upgrading your procps, there's a chance it's just so ancient thatit accidentally got broken. However, if that fixes your problem, thenplease report back with a subject line of "/proc API breakage" orsomesuch, to get the proper attention to the issue.ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

Re: high %CPU values after upgrading to the last stable kernel

[Alistair John Strachan]

On Wednesday 22 October 2008 23:40:54 Ray Lee wrote:
> On Wed, Oct 22, 2008 at 2:04 PM, Frédéric Weisbecker <fweisbec@gmail.com> 
wrote:
> > 2008/10/22 sbs <gexlie@gmail.com>:
[snip]
> >> should i upgrade procps or downgrade kernel then to get proper values
> >> back? :) or is it a feature of the new kernel?
> >>
> >> thank you
> >
> > Hi,
> >
> > It really depends on what your box is doing at the time you capture
> > the cpu usage.
> > And it really depends too of your kernel config...
>
> It really shouldn't, we're talking about /proc which is supposed to be
> a stable userspace interface.
>
> Try upgrading your procps, there's a chance it's just so ancient that
> it accidentally got broken. However, if that fixes your problem, then
> please report back with a subject line of "/proc API breakage" or
> somesuch, to get the proper attention to the issue.

This is a known kernel bug that for some reason wasn't fixed before 2.6.27 was 
released. See http://bugzilla.kernel.org/show_bug.cgi?id=11209 for details.

It would probably be useful if the OP added himself to the CC list, so Peter 
can get some more details about the box.

-- 
Cheers,
Alistair.

Re: high %CPU values after upgrading to the last stable kernel

[sbs]

thank you
will be waiting until it gets fixed

On Thu, Oct 23, 2008 at 4:55 AM, Alistair John Strachan
<alistair@devzero.co.uk> wrote:
> On Wednesday 22 October 2008 23:40:54 Ray Lee wrote:
>> On Wed, Oct 22, 2008 at 2:04 PM, Frédéric Weisbecker <fweisbec@gmail.com>
> wrote:
>> > 2008/10/22 sbs <gexlie@gmail.com>:
> [snip]
>> >> should i upgrade procps or downgrade kernel then to get proper values
>> >> back? :) or is it a feature of the new kernel?
>> >>
>> >> thank you
>> >
>> > Hi,
>> >
>> > It really depends on what your box is doing at the time you capture
>> > the cpu usage.
>> > And it really depends too of your kernel config...
>>
>> It really shouldn't, we're talking about /proc which is supposed to be
>> a stable userspace interface.
>>
>> Try upgrading your procps, there's a chance it's just so ancient that
>> it accidentally got broken. However, if that fixes your problem, then
>> please report back with a subject line of "/proc API breakage" or
>> somesuch, to get the proper attention to the issue.
>
> This is a known kernel bug that for some reason wasn't fixed before 2.6.27 was
> released. See http://bugzilla.kernel.org/show_bug.cgi?id=11209 for details.
>
> It would probably be useful if the OP added himself to the CC list, so Peter
> can get some more details about the box.
>
> --
> Cheers,
> Alistair.
>