hyperic-hq-discuss

[Hyperic-hq-discuss] Sigar.getProcCpu(id) returns invalid data

[guy_vt <sig...@hy...>]

I want to use Sigar to monitor a running process for CPU load. So far I have only gotten values smaller than 1 percent. So I wanted to test how it would handle higher CPU values and whether it gave correct values under load. It would appear that it doesnt:

I am using the following code:

try
		{
			Sigar sigar = new Sigar();
			long id = sigar.getPid();
			ProcCpu cpu = sigar.getProcCpu(id);
			System.out.println(cpu.toString());
			
			while (true)
			{
				cpu = sigar.getProcCpu(id);
				System.out.println("cpu=" + cpu.toString());
			}
		}
		catch (Exception e)
		{
			e.printStackTrace();
		}


I get the following output:

cpu={LastTime=1276071236204, StartTime=1276071231143, Percent=8.504036623604765E-299, Sys=296, User=1388, Total=1684}
cpu={LastTime=1276071236204, StartTime=1276071231143, Percent=8.504036623604765E-299, Sys=296, User=1388, Total=1684}
cpu={LastTime=1276071236205, StartTime=1276071231143, Percent=16.0, Sys=312, User=1388, Total=1700}

As you can see it occasionnaly returns 15-16% but appart from that it returns a rediculously low values. Another problem is dat the javaw (I run under Eclipse) process consumes more than the 15-16% !

I am running on Windows Vista using a Sun java 1.5.0_15

Re: [Hyperic-hq-discuss] Sigar.getProcCpu(id) returns invalid data

[Doug M. <do...@hy...>]

You should have add a Thread.sleep(1000) in the while (true) loop, give or take on the interval.

Re: [Hyperic-hq-discuss] Sigar.getProcCpu(id) returns invalid data

[guy_vt <sig...@hy...>]

Do you mean to tell me that Sigar is unable to detect high CPU loads of the running process?

Re: [Hyperic-hq-discuss] Sigar.getProcCpu(id) returns invalid data

[jrallen9 <jus...@te...>]

I think there is a logic flaw in your test case.

The program you've written is I/O bound on the output to the display. The CPU has far more throughput then the buffers present for stdout. 

You might want to do a comparison by getting the overall system utilization from the CpuPerc class. Use the Sigar.getCpuPercList() to do a summation calculation from the array of CpuPerc (Intel Gulftown processors can have up to 12 logical cores). Use 1 - Idle formula to get the overall system CPU load.

Compare the above busy calculation to the ProcCpu values. They should be roughly similar.

Another possibility is to run a computationally intensive program like Prime95 or equivalent on the system, take note of the PID using taskmanger or the ps command on linux and use that as the PID for your program.

My development has shown the SIGAR code CPU values are accurate.

Re: [Hyperic-hq-discuss] Sigar.getProcCpu(id) returns invalid data

[slopixi <sig...@hy...>]

Hi, 

I'll continue this thread, I'm having problems with getting really small process cpu usages. 

My program is running on HPUX and does give me accurate data for process usages that are high. 

I have problem that I can't get usages that are < 1%. They are just 0.0%. 

I know the problem getting in loop etc. Because I'm getting data for higher usages.

My problem is not crashing type, but its really annoying. 

Way I get the data: 

class extends SigarCommandBase

in class there is loop that gets data

ProcCpu procCPU = this.proxy.getProcCpu( pid);
procCPU.getPercent()*100;

 There is 2s between data reading.

I'll be really greateful for any suggestion.