/* latency.h -- latency monitor API header file * See latency.c for more information. * * ---------------------------------------------------------------------------- * * Copyright (c) 2014-Present, Redis Ltd. * All rights reserved. * * Licensed under your choice of the Redis Source Available License 2.0 * (RSALv2) or the Server Side Public License v1 (SSPLv1). */ #ifndef __LATENCY_H #define __LATENCY_H #define LATENCY_TS_LEN 160 /* History length for every monitored event. */ /* Representation of a latency sample: the sampling time and the latency * observed in milliseconds. */ struct latencySample { int32_t time; /* We don't use time_t to force 4 bytes usage everywhere. */ uint32_t latency; /* Latency in milliseconds. */ }; /* The latency time series for a given event. */ struct latencyTimeSeries { int idx; /* Index of the next sample to store. */ uint32_t max; /* Max latency observed for this event. */ struct latencySample samples[LATENCY_TS_LEN]; /* Latest history. */ }; /* Latency statistics structure. */ struct latencyStats { uint32_t all_time_high; /* Absolute max observed since latest reset. */ uint32_t avg; /* Average of current samples. */ uint32_t min; /* Min of current samples. */ uint32_t max; /* Max of current samples. */ uint32_t mad; /* Mean absolute deviation. */ uint32_t samples; /* Number of non-zero samples. */ time_t period; /* Number of seconds since first event and now. */ }; void latencyMonitorInit(void); void latencyAddSample(const char *event, mstime_t latency); /* Latency monitoring macros. */ /* Start monitoring an event. We just set the current time. */ #define latencyStartMonitor(var) if (server.latency_monitor_threshold) { \ var = mstime(); \ } else { \ var = 0; \ } /* End monitoring an event, compute the difference with the current time * to check the amount of time elapsed. */ #define latencyEndMonitor(var) if (server.latency_monitor_threshold) { \ var = mstime() - var; \ } /* Add the sample only if the elapsed time is >= to the configured threshold. */ #define latencyAddSampleIfNeeded(event,var) \ if (server.latency_monitor_threshold && \ (var) >= server.latency_monitor_threshold) \ latencyAddSample((event),(var)); /* Remove time from a nested event. */ #define latencyRemoveNestedEvent(event_var,nested_var) \ event_var += nested_var; typedef struct durationStats { unsigned long long cnt; unsigned long long sum; unsigned long long max; } durationStats; typedef enum { EL_DURATION_TYPE_EL = 0, // cumulative time duration metric of the whole eventloop EL_DURATION_TYPE_CMD, // cumulative time duration metric of executing commands EL_DURATION_TYPE_AOF, // cumulative time duration metric of flushing AOF in eventloop EL_DURATION_TYPE_CRON, // cumulative time duration metric of cron (serverCron and beforeSleep, but excluding IO and AOF) EL_DURATION_TYPE_NUM } DurationType; void durationAddSample(int type, monotime duration); #endif /* __LATENCY_H */