adb command cpu 100%

[go3mon]

I have a 100% cpu on my server.
Is it normal for this process?:

Load averages: 1.22, 1.53, 1.58
132 processes: 110 sleeping, 22 running
Cpu states:
LOAD USER NICE SYS IDLE BLOCK SWAIT INTR SSYS
1.22 43.9% 0.0% 56.1% 0.0% 0.0% 0.0% 0.0% 0.0%

Memory: 399868K (301488K) real, 708728K (570408K) virtual, 1820252K free Page# 1/4

TTY PID USERNAME PRI NI SIZE RES STATE TIME %WCPU %CPU COMMAND
? 9269 root 228 20 33160K 4672K run 202:06 93.26 93.10 adb

What adb process do?

[Reshma Malusare · Accepted solution]

Hi,
adb is absolute debugger.
The adb command executes a general-purpose debugging program that is sensitive to the underlying architecture of the processor and operating system on which it runs. It can be used to examine files and provide a controlled environment for executing HP-UX programs.

adb inspects exactly one object file, referred to as the current object file, and one memory file, referred to as the current memory file. Either of these files can be the NULL file, specified by the - argument, which is a file with no contents

Syntax:

adb [-h]

adb [-n|-o] [-w] [-I path] kernelfile memfile

adb [-n|-o] [-w] [-I path] kernelfile crashdir

adb [-n|-o] [-w] [-I path] crashdir

adb [-n|-o] [-w] [-I path] [objfile] [corefile]

adb [-n|-o] [-w] [-I path] -P pid [execfile


-h Print a usage summary and exit. If this option is used, all other options and arguments are ignored.

-I path path specifies a list of directories where files read with < or << (see below) are sought. This list has the same syntax as, and similar semantics to, the PATH shell variable; the default is .:/usr/lib/adb.

-n Specify the normal mode. This is the default on Itanium systems. This option is mutually exclusive with the -o option. The last one specified takes effect.

-o Specify backward compatibility mode. This is the default on PA systems. This option is mutually exclusive with the -n option. The last one specified takes effect.

-P pid Adopt process with process ID pid as a ``traced'' process; see ttrace(2). This option is helpful for debugging processes that were not originally run under the control of adb.

-w This option must be specified to enable the file write commands of adb. Objfile is opened for reading and writing. It also enables writes to memfile if it is a kernel memory file.

Regards
Reshma

[go3mon]

These are the command launched on the server:

root /=>ps -ef | grep adb
root 9269 9267 189 23:01:50 ? 232:12 adb /stand/vmunix /dev/mem
root 9267 9216 0 23:01:50 ? 0:00 sh -c echo itick_per_usec/D | adb /stand/vmunix /dev/mem | tail


Can I do anythink to reduce cpu usage?

[Reshma Malusare]

Hi,
/stand/vmunix is kernel & /dev/mem are memory files. so please check before excuting any command.

please refer following link,which may help you.

http://docs.hp.com/en/J2237-90005/ch06s06.html?jumpid=reg_R1002_USEN

[Reshma Malusare]

Hi,
Read follwing:
Kernel level debugging is associated with the hardware that a kernel is running on. The kernel level debugging tools are different for the different hardware platforms.

For the Series 700, kernel level debugging may be performed using ddb. ddb can be used to set breakpoints, single-step through code, examine the contents of data structures at key points, change the contents of structures and variables, and use most other normal debugging techniques. ddb is documented in HP-UX Driver Development Guide, part number 98577-90013. ddb is not part of the standard Series 700 HP-UX product. To obtain a copy of ddb software, contact your HP representative.

For Series 700 and 800, kernel level debugging may be performed using adb, which is a general purpose assembly language debugging program. adb allows you to look at HP-UX files and system core files that result from system panics, to examine system registers and memory locations as they were at the time of the panic, and to print data from these files in a variety of formats. adb can also be used to examine a running HP-UX system. adb is part of the standard HP-UX product and is located in
/usr/bin on every HP-UX system. It is important to use the revision of adb which corresponds with the release of the kernel being debugged -- for example, a 9.0 version of adb will not work well on a 10.0 kernel

Regards
Reshma

[Reshma Malusare]

Hi,
When using adb on a running HP-UX system, you also use the "-k" option, and use /stand/vmunix as the object file and /dev/mem as the core file:


adb -k /stand/vmunix /dev/mem


You will probably need to be superuser to access /dev/mem. Because you are examining a running (and continuously changing) system, adb will not be able to set you up in any specific process context, but you will be able to examine kernel global variables.

[Reshma Malusare]

Hi go3mon,
Can you please assign points if your query is solved.

Thanks & Regards
Reshma

[Dennis Handly]

Ordinarily, I woudn't expect adb to take that amount of time. Can you show the whole process tree? Who is the parent 9216 and its parent, etc.

Are they in a shell loop that keeps invoking adb? (But that would show the shell in a loop and multiple adb processes.)

For 11.23, I had to use:
echo "itick_per_usec/D" | adb -o /stand/vmunix /dev/kmem