From: hufh@Lenovo.com - 2004-01-31 10:43:48
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Hi,all: I want to get a kernel function's execution time during a certain term, but i found my Xeon have only GLOBAL_POWER_EVENTS, no CPU_CLK_UNHALTED, the latter appears in P6 performance event lists. Are the two events same? and how can i measure functions' exectuion time? Thanks in advance. Best Regards! Yours Sincerely hufh |
From: William C. <wc...@nc...> - 2004-01-31 14:54:51
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hufh@Lenovo.com wrote: > Hi,all: > I want to get a kernel function's execution time during a certain term, > but i found my Xeon have only GLOBAL_POWER_EVENTS, no CPU_CLK_UNHALTED, > the latter appears in P6 performance event lists. > Are the two events same? and how can i measure functions' exectuion time? > Thanks in advance. > Best Regards! GLOBAL_POWER_EVENTS on the P4 is equivalent to the CPU_CLK_UNHALTED on the P6. OProfile does not directly measure the time spent in functions. However, you can compute the amount of a sample represents and multiple the number of samples for a function to get an estimate of the time spent in the function. For example P4 processor clock rate is 2.4GHz and the sampling is set to 500000 GLOBAL_POWER_EVENTS per sample, each sample is 500000/2.4GHz=2.08 milliseconds. Thus, if a function has 30,000 samples one would estimate that 6.25 seconds was spent in that function. -Will > > Yours Sincerely > hufh > > > > > ------------------------------------------------------- > The SF.Net email is sponsored by EclipseCon 2004 > Premiere Conference on Open Tools Development and Integration > See the breadth of Eclipse activity. February 3-5 in Anaheim, CA. > http://www.eclipsecon.org/osdn > _______________________________________________ > oprofile-list mailing list > opr...@li... > https://lists.sourceforge.net/lists/listinfo/oprofile-list > |