redis-cli --latency: ability to run non interactively.

This feature was proposed by @rosmo in PR #2643 and later redesigned
in order to fit better with the other options for non-interactive modes
of redis-cli. The idea is basically to allow to collect latency
information in scripts, cron jobs or whateever, just running for a
limited time and then producing a single output.
This commit is contained in:
antirez 2017-06-30 15:41:58 +02:00
parent 7bad78bd2f
commit 26e638a8e9

View File

@ -1123,6 +1123,12 @@ static void usage(void) {
" --csv Output in CSV format.\n"
" --stat Print rolling stats about server: mem, clients, ...\n"
" --latency Enter a special mode continuously sampling latency.\n"
" If you use this mode in an interactive session it runs\n"
" forever displaying real-time stats. Otherwise if --raw or\n"
" --csv is specified, or if you redirect the output to a non\n"
" TTY, it samples the latency for 1 second (you can use\n"
" -i to change the interval), then produces a single output\n"
" and exits.\n"
" --latency-history Like --latency but tracking latency changes over time.\n"
" Default time interval is 15 sec. Change it using -i.\n"
" --latency-dist Shows latency as a spectrum, requires xterm 256 colors.\n"
@ -1472,6 +1478,18 @@ static int evalMode(int argc, char **argv) {
* Latency and latency history modes
*--------------------------------------------------------------------------- */
static void latencyModePrint(long long min, long long max, double avg, long long count) {
if (config.output == OUTPUT_STANDARD) {
printf("min: %lld, max: %lld, avg: %.2f (%lld samples)",
min, max, avg, count);
fflush(stdout);
} else if (config.output == OUTPUT_CSV) {
printf("%lld,%lld,%.2f,%lld\n", min, max, avg, count);
} else if (config.output == OUTPUT_RAW) {
printf("%lld %lld %.2f %lld\n", min, max, avg, count);
}
}
#define LATENCY_SAMPLE_RATE 10 /* milliseconds. */
#define LATENCY_HISTORY_DEFAULT_INTERVAL 15000 /* milliseconds. */
static void latencyMode(void) {
@ -1483,6 +1501,14 @@ static void latencyMode(void) {
double avg;
long long history_start = mstime();
/* Set a default for the interval in case of --latency option
* with --raw, --csv or when it is redirected to non tty. */
if (config.interval == 0) {
config.interval = 1000;
} else {
config.interval /= 1000; /* We need to convert to milliseconds. */
}
if (!context) exit(1);
while(1) {
start = mstime();
@ -1503,9 +1529,19 @@ static void latencyMode(void) {
tot += latency;
avg = (double) tot/count;
}
printf("\x1b[0G\x1b[2Kmin: %lld, max: %lld, avg: %.2f (%lld samples)",
min, max, avg, count);
fflush(stdout);
if (config.output == OUTPUT_STANDARD) {
printf("\x1b[0G\x1b[2K"); /* Clear the line. */
latencyModePrint(min,max,avg,count);
} else {
if (config.latency_history) {
latencyModePrint(min,max,avg,count);
} else if (mstime()-history_start > config.interval) {
latencyModePrint(min,max,avg,count);
exit(0);
}
}
if (config.latency_history && mstime()-history_start > history_interval)
{
printf(" -- %.2f seconds range\n", (float)(mstime()-history_start)/1000);