"Fossies" - the Fresh Open Source Software Archive  

Source code changes of the file "rd_stats.c" between
sysstat-12.4.0.tar.xz and sysstat-12.4.1.tar.xz

About: sysstat is a collection of performance monitoring tools for Linux including amongst others sar (collects and reports system activity) and iostat (reports CPU statistics and I/O statistics for tty devices and disks). Stable version.

rd_stats.c  (sysstat-12.4.0.tar.xz)	:	rd_stats.c  (sysstat-12.4.1.tar.xz)
skipping to change at line 443		skipping to change at line 443
* Workaround for CPU coming back online: With recent kernels		* Workaround for CPU coming back online: With recent kernels
* some fields (user, nice, system) restart from their previous value,		* some fields (user, nice, system) restart from their previous value,
* whereas others (idle, iowait) restart from zero.		* whereas others (idle, iowait) restart from zero.
* For the latter we need to set their previous value to zero to		* For the latter we need to set their previous value to zero to
* avoid getting an interval value < 0.		* avoid getting an interval value < 0.
* (I don't know how the other fields like hardirq, steal... behave).		* (I don't know how the other fields like hardirq, steal... behave).
* Don't assume the CPU has come back from offline state if previous		* Don't assume the CPU has come back from offline state if previous
* value was greater than ULLONG_MAX - 0x7ffff (the counter probably		* value was greater than ULLONG_MAX - 0x7ffff (the counter probably
* overflew).		* overflew).
*/		*/
		if ((scc->cpu_iowait < scp->cpu_iowait) && (scp->cpu_iowait < (ULLONG_MAX
		- 0x7ffff))) {
		/*
		* The iowait value reported by the kernel can also decrement as
		* a result of inaccurate iowait tracking. Waiting on IO can be
		* first accounted as iowait but then instead as idle.
		* Therefore if the idle value during the same period did not
		* decrease then consider this is a problem with the iowait
		* reporting and correct the previous value according to the new
		* reading. Otherwise, treat this as CPU coming back online.
		*/
		if ((scc->cpu_idle > scp->cpu_idle) || (scp->cpu_idle >= (ULLONG_
		MAX - 0x7ffff))) {
		scp->cpu_iowait = scc->cpu_iowait;
		}
		else {
		scp->cpu_iowait = 0;
		}
		}
if ((scc->cpu_idle < scp->cpu_idle) && (scp->cpu_idle < (ULLONG_MAX - 0x7 ffff))) {		if ((scc->cpu_idle < scp->cpu_idle) && (scp->cpu_idle < (ULLONG_MAX - 0x7 ffff))) {
scp->cpu_idle = 0;		scp->cpu_idle = 0;
}		}
if ((scc->cpu_iowait < scp->cpu_iowait) && (scp->cpu_iowait < (ULLONG_MAX
- 0x7ffff))) {
scp->cpu_iowait = 0;
}
/*		/*
* Don't take cpu_guest and cpu_guest_nice into account		* Don't take cpu_guest and cpu_guest_nice into account
* because cpu_user and cpu_nice already include them.		* because cpu_user and cpu_nice already include them.
*/		*/
return ((scc->cpu_user + scc->cpu_nice +		return ((scc->cpu_user + scc->cpu_nice +
scc->cpu_sys + scc->cpu_iowait +		scc->cpu_sys + scc->cpu_iowait +
scc->cpu_idle + scc->cpu_steal +		scc->cpu_idle + scc->cpu_steal +
scc->cpu_hardirq + scc->cpu_softirq) -		scc->cpu_hardirq + scc->cpu_softirq) -
(scp->cpu_user + scp->cpu_nice +		(scp->cpu_user + scp->cpu_nice +
End of changes. 2 change blocks.
4 lines changed or deleted		19 lines changed or added

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