Date: Tue, 31 Jul 2012 18:57:09 +0000 From: rudot@FreeBSD.org To: svn-soc-all@FreeBSD.org Subject: socsvn commit: r239963 - soc2012/rudot/sys/kern Message-ID: <20120731185709.13CF9106566C@hub.freebsd.org>
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Author: rudot Date: Tue Jul 31 18:57:08 2012 New Revision: 239963 URL: http://svnweb.FreeBSD.org/socsvn/?view=rev&rev=239963 Log: use special way to calculate %cpu for short-lived processes. Work in progress. Modified: soc2012/rudot/sys/kern/kern_racct.c Modified: soc2012/rudot/sys/kern/kern_racct.c ============================================================================== --- soc2012/rudot/sys/kern/kern_racct.c Tue Jul 31 17:32:28 2012 (r239962) +++ soc2012/rudot/sys/kern/kern_racct.c Tue Jul 31 18:57:08 2012 (r239963) @@ -282,7 +282,7 @@ * work. */ static u_int -racct_getpcpu(struct proc *p) +racct_getpcpu(struct proc *p, u_int pcpu) { u_int swtime; #ifdef SCHED_4BSD @@ -298,6 +298,14 @@ swtime = (ticks - p->p_swtick) / hz; if ((swtime == 0) || ((p->p_flag & P_INMEM) == 0)) return (0); + if (swtime < 20) { + /* + * For short-lived processes, the sched_pctcpu() returns small + * values even for cpu intensive processes. Therefore we use + * our own estimate in this case. + */ + return (pcpu); + } p_pctcpu = 0; FOREACH_THREAD_IN_PROC(p, td) { @@ -1002,7 +1010,7 @@ struct proc *p; struct timeval wallclock; uint64_t runtime; - u_int pct; + u_int pct, pct_estimate; int over_limits; for (;;) { @@ -1036,7 +1044,10 @@ runtime = p->p_prev_runtime; #endif p->p_prev_runtime = runtime; - pct = racct_getpcpu(p); + pct_estimate = (runtime * 100) / + ((uint64_t)wallclock.tv_sec * 1000000 + + wallclock.tv_usec); + pct = racct_getpcpu(p, pct_estimate); mtx_lock(&racct_lock); over_limits = racct_set_check_locked(p, RACCT_PCTCPU, pct); if (over_limits) {
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