Author: cperciva Date: Sat Feb 29 22:31:23 2020 New Revision: 358478 URL: https://svnweb.freebsd.org/changeset/base/358478
Log: Add -N option to powerd(8) to ignore "nice" time. With powerd_flags="-N", this makes powerd(8) exclude "nice" time when computing the CPU utilization. This makes it possible to prevent CPU-intensive "background" processes from spinning up the CPU. Note that only *userland* CPU usage belonging to "nice" processes is excluded; we do not track whether time spent in the kernel is on behalf of nice or non-nice processes, so kernel-intensive nice processes can still result in the CPU being sped up. MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D23868 Modified: head/usr.sbin/powerd/powerd.8 head/usr.sbin/powerd/powerd.c Modified: head/usr.sbin/powerd/powerd.8 ============================================================================== --- head/usr.sbin/powerd/powerd.8 Sat Feb 29 22:16:27 2020 (r358477) +++ head/usr.sbin/powerd/powerd.8 Sat Feb 29 22:31:23 2020 (r358478) @@ -37,6 +37,7 @@ .Op Fl i Ar percent .Op Fl m Ar freq .Op Fl M Ar freq +.Op Fl N .Op Fl n Ar mode .Op Fl p Ar ival .Op Fl P Ar pidfile @@ -102,6 +103,10 @@ The default is 50% or lower. Specifies the minimum frequency to throttle down to. .It Fl M Ar freq Specifies the maximum frequency to throttle up to. +.It Fl N +Treat "nice" time as idle for the purpose of load calculation; +i.e. do not increase the CPU frequency if the CPU is only busy +with "nice" processes. .It Fl n Ar mode Selects the .Ar mode Modified: head/usr.sbin/powerd/powerd.c ============================================================================== --- head/usr.sbin/powerd/powerd.c Sat Feb 29 22:16:27 2020 (r358477) +++ head/usr.sbin/powerd/powerd.c Sat Feb 29 22:31:23 2020 (r358478) @@ -86,7 +86,7 @@ static const char *modes[] = { #define DEVDPIPE "/var/run/devd.pipe" #define DEVCTL_MAXBUF 1024 -static int read_usage_times(int *load); +static int read_usage_times(int *load, int nonice); static int read_freqs(int *numfreqs, int **freqs, int **power, int minfreq, int maxfreq); static int set_freq(int freq); @@ -135,15 +135,17 @@ static struct timeval tried_devd; * This function returns summary load of all CPUs. It was made so * intentionally to not reduce performance in scenarios when several * threads are processing requests as a pipeline -- running one at - * a time on different CPUs and waiting for each other. + * a time on different CPUs and waiting for each other. If nonice + * is nonzero, only user+sys+intr time will be counted as load; any + * nice time will be treated as if idle. */ static int -read_usage_times(int *load) +read_usage_times(int *load, int nonice) { static long *cp_times = NULL, *cp_times_old = NULL; static int ncpus = 0; size_t cp_times_len; - int error, cpu, i, total; + int error, cpu, i, total, excl; if (cp_times == NULL) { cp_times_len = 0; @@ -175,8 +177,12 @@ read_usage_times(int *load) } if (total == 0) continue; - *load += 100 - (cp_times[cpu * CPUSTATES + CP_IDLE] - - cp_times_old[cpu * CPUSTATES + CP_IDLE]) * 100 / total; + excl = cp_times[cpu * CPUSTATES + CP_IDLE] - + cp_times_old[cpu * CPUSTATES + CP_IDLE]; + if (nonice) + excl += cp_times[cpu * CPUSTATES + CP_NICE] - + cp_times_old[cpu * CPUSTATES + CP_NICE]; + *load += 100 - excl * 100 / total; } } @@ -473,7 +479,7 @@ usage(void) { fprintf(stderr, -"usage: powerd [-v] [-a mode] [-b mode] [-i %%] [-m freq] [-M freq] [-n mode] [-p ival] [-r %%] [-s source] [-P pidfile]\n"); +"usage: powerd [-v] [-a mode] [-b mode] [-i %%] [-m freq] [-M freq] [-N] [-n mode] [-p ival] [-r %%] [-s source] [-P pidfile]\n"); exit(1); } @@ -490,6 +496,7 @@ main(int argc, char * argv[]) int ch, mode, mode_ac, mode_battery, mode_none, idle, to; uint64_t mjoules_used; size_t len; + int nonice; /* Default mode for all AC states is adaptive. */ mode_ac = mode_none = MODE_HIADAPTIVE; @@ -499,12 +506,13 @@ main(int argc, char * argv[]) poll_ival = DEFAULT_POLL_INTERVAL; mjoules_used = 0; vflag = 0; + nonice = 0; /* User must be root to control frequencies. */ if (geteuid() != 0) errx(1, "must be root to run"); - while ((ch = getopt(argc, argv, "a:b:i:m:M:n:p:P:r:s:v")) != -1) + while ((ch = getopt(argc, argv, "a:b:i:m:M:Nn:p:P:r:s:v")) != -1) switch (ch) { case 'a': parse_mode(optarg, &mode_ac, ch); @@ -539,6 +547,9 @@ main(int argc, char * argv[]) usage(); } break; + case 'N': + nonice = 1; + break; case 'n': parse_mode(optarg, &mode_none, ch); break; @@ -584,7 +595,7 @@ main(int argc, char * argv[]) err(1, "lookup freq_levels"); /* Check if we can read the load and supported freqs. */ - if (read_usage_times(NULL)) + if (read_usage_times(NULL, nonice)) err(1, "read_usage_times"); if (read_freqs(&numfreqs, &freqs, &mwatts, minfreq, maxfreq)) err(1, "error reading supported CPU frequencies"); @@ -766,7 +777,7 @@ main(int argc, char * argv[]) } /* Adaptive mode; get the current CPU usage times. */ - if (read_usage_times(&load)) { + if (read_usage_times(&load, nonice)) { if (vflag) warn("read_usage_times() failed"); continue; _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
