#include "common.h"
+// ----------------------------------------------------------------------------
+// How backends work in netdata:
+//
+// 1. There is an independent thread that runs at the required interval
+// (for example, once every 10 seconds)
+//
+// 2. Every time it wakes, it calls the backend formatting functions to build
+// a buffer of data. This is a very fast, memory only operation.
+//
+// 3. If the buffer already includes data, the new data are appended.
+// If the buffer becomes too big, because the data cannot be sent, a
+// log is written and the buffer is discarded.
+//
+// 4. Then it tries to send all the data. It blocks until all the data are sent
+// or the socket returns an error.
+// If the time required for this is above the interval, it starts skipping
+// intervals, but the calculated values include the entire database, without
+// gaps (it remembers the timestamps and continues from where it stopped).
+//
+// 5. repeats the above forever.
+//
+
#define BACKEND_SOURCE_DATA_AS_COLLECTED 0x00000001
#define BACKEND_SOURCE_DATA_AVERAGE 0x00000002
#define BACKEND_SOURCE_DATA_SUM 0x00000004
-static inline calculated_number backend_calculate_value_from_stored_data(RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+
+// ----------------------------------------------------------------------------
+// helper functions for backends
+
+// calculate the SUM or AVERAGE of a dimension, for any timeframe
+// may return NAN if the database does not have any value in the give timeframe
+
+static inline calculated_number backend_calculate_value_from_stored_data(
+ RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
+ // find the edges of the rrd database for this chart
time_t first_t = rrdset_first_entry_t(st);
- time_t last_t = rrdset_last_entry_t(st);
+ time_t last_t = rrdset_last_entry_t(st);
if(unlikely(before < first_t || after > last_t))
// the chart has not been updated in the wanted timeframe
after = first_t;
if(unlikely(after > before))
- // this can happen when the st->update_every > before - after
+ // this can happen when st->update_every > before - after
before = after;
if(unlikely(before > last_t))
slot, stop_now = 0;
for(slot = start_at_slot; !stop_now ; slot--) {
+
if(unlikely(slot < 0)) slot = st->entries - 1;
if(unlikely(slot == stop_at_slot)) stop_now = 1;
storage_number n = rd->values[slot];
- if(unlikely(!does_storage_number_exist(n))) continue;
+
+ if(unlikely(!does_storage_number_exist(n))) {
+ // not collected
+ continue;
+ }
calculated_number value = unpack_storage_number(n);
sum += value;
+
counter++;
}
return sum / (calculated_number)counter;
}
-static inline int format_dimension_collected_graphite_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+
+// discard a response received by a backend
+// after logging a simple of it to error.log
+
+static inline int discard_response(BUFFER *b, const char *backend) {
+ char sample[1024];
+ const char *s = buffer_tostring(b);
+ char *d = sample, *e = &sample[sizeof(sample) - 1];
+
+ for(; *s && d < e ;s++) {
+ char c = *s;
+ if(unlikely(!isprint(c))) c = ' ';
+ *d++ = c;
+ }
+ *d = '\0';
+
+ info("Received %zu bytes from %s backend. Ignoring them. Sample: '%s'", buffer_strlen(b), backend, sample);
+ buffer_flush(b);
+ return 0;
+}
+
+
+// ----------------------------------------------------------------------------
+// graphite backend
+
+static inline int format_dimension_collected_graphite_plaintext(
+ BUFFER *b // the buffer to write data to
+ , const char *prefix // the prefix to use
+ , RRDHOST *host // the host this chart comes from
+ , const char *hostname // the hostname (to override host->hostname)
+ , RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
(void)host;
(void)after;
(void)before;
(void)options;
- buffer_sprintf(b, "%s.%s.%s.%s " COLLECTED_NUMBER_FORMAT " %u\n", prefix, hostname, st->id, rd->id, rd->last_collected_value, (uint32_t)rd->last_collected_time.tv_sec);
+
+ buffer_sprintf(
+ b
+ , "%s.%s.%s.%s " COLLECTED_NUMBER_FORMAT " %u\n"
+ , prefix
+ , hostname
+ , st->id
+ , rd->id
+ , rd->last_collected_value
+ , (uint32_t)rd->last_collected_time.tv_sec
+ );
+
return 1;
}
-static inline int format_dimension_stored_graphite_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+static inline int format_dimension_stored_graphite_plaintext(
+ BUFFER *b // the buffer to write data to
+ , const char *prefix // the prefix to use
+ , RRDHOST *host // the host this chart comes from
+ , const char *hostname // the hostname (to override host->hostname)
+ , RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
(void)host;
+
calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, options);
+
if(!isnan(value)) {
- buffer_sprintf(b, "%s.%s.%s.%s " CALCULATED_NUMBER_FORMAT " %u\n", prefix, hostname, st->id, rd->id, value, (uint32_t) before);
+
+ buffer_sprintf(
+ b
+ , "%s.%s.%s.%s " CALCULATED_NUMBER_FORMAT " %u\n"
+ , prefix
+ , hostname
+ , st->id
+ , rd->id
+ , value
+ , (uint32_t) before
+ );
+
return 1;
}
return 0;
}
-static inline int format_dimension_collected_opentsdb_telnet(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+static inline int process_graphite_response(BUFFER *b) {
+ return discard_response(b, "graphite");
+}
+
+
+// ----------------------------------------------------------------------------
+// opentsdb backend
+
+static inline int format_dimension_collected_opentsdb_telnet(
+ BUFFER *b // the buffer to write data to
+ , const char *prefix // the prefix to use
+ , RRDHOST *host // the host this chart comes from
+ , const char *hostname // the hostname (to override host->hostname)
+ , RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
(void)host;
(void)after;
(void)before;
(void)options;
- buffer_sprintf(b, "put %s.%s.%s %u " COLLECTED_NUMBER_FORMAT " host=%s\n", prefix, st->id, rd->id, (uint32_t)rd->last_collected_time.tv_sec, rd->last_collected_value, hostname);
+
+ buffer_sprintf(
+ b
+ , "put %s.%s.%s %u " COLLECTED_NUMBER_FORMAT " host=%s\n"
+ , prefix
+ , st->id
+ , rd->id
+ , (uint32_t)rd->last_collected_time.tv_sec
+ , rd->last_collected_value
+ , hostname
+ );
+
return 1;
}
-static inline int format_dimension_stored_opentsdb_telnet(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+static inline int format_dimension_stored_opentsdb_telnet(
+ BUFFER *b // the buffer to write data to
+ , const char *prefix // the prefix to use
+ , RRDHOST *host // the host this chart comes from
+ , const char *hostname // the hostname (to override host->hostname)
+ , RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
(void)host;
+
calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, options);
+
if(!isnan(value)) {
- buffer_sprintf(b, "put %s.%s.%s %u " CALCULATED_NUMBER_FORMAT " host=%s\n", prefix, st->id, rd->id, (uint32_t) before, value, hostname);
+
+ buffer_sprintf(
+ b
+ , "put %s.%s.%s %u " CALCULATED_NUMBER_FORMAT " host=%s\n"
+ , prefix
+ , st->id
+ , rd->id
+ , (uint32_t) before
+ , value
+ , hostname
+ );
+
return 1;
}
return 0;
}
-static inline int format_dimension_collected_json_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+static inline int process_opentsdb_response(BUFFER *b) {
+ return discard_response(b, "opentsdb");
+}
+
+
+// ----------------------------------------------------------------------------
+// json backend
+
+static inline int format_dimension_collected_json_plaintext(
+ BUFFER *b // the buffer to write data to
+ , const char *prefix // the prefix to use
+ , RRDHOST *host // the host this chart comes from
+ , const char *hostname // the hostname (to override host->hostname)
+ , RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
(void)host;
(void)after;
(void)before;
(void)options;
+
buffer_sprintf(b, "{"
"\"prefix\":\"%s\","
"\"hostname\":\"%s\","
"\"timestamp\": %u}\n",
prefix,
hostname,
-
+
st->id,
st->name,
st->family,
rd->id,
rd->name,
- rd->last_collected_value,
-
+ rd->last_collected_value,
+
(uint32_t)rd->last_collected_time.tv_sec
);
return 1;
}
-static inline int format_dimension_stored_json_plaintext(BUFFER *b, const char *prefix, RRDHOST *host, const char *hostname, RRDSET *st, RRDDIM *rd, time_t after, time_t before, uint32_t options) {
+static inline int format_dimension_stored_json_plaintext(
+ BUFFER *b // the buffer to write data to
+ , const char *prefix // the prefix to use
+ , RRDHOST *host // the host this chart comes from
+ , const char *hostname // the hostname (to override host->hostname)
+ , RRDSET *st // the chart
+ , RRDDIM *rd // the dimension
+ , time_t after // the start timestamp
+ , time_t before // the end timestamp
+ , uint32_t options // BACKEND_SOURCE_* bitmap
+) {
(void)host;
+
calculated_number value = backend_calculate_value_from_stored_data(st, rd, after, before, options);
+
if(!isnan(value)) {
buffer_sprintf(b, "{"
"\"prefix\":\"%s\","
return 0;
}
-static inline int process_graphite_response(BUFFER *b) {
- char sample[1024];
- const char *s = buffer_tostring(b);
- char *d = sample, *e = &sample[sizeof(sample) - 1];
-
- for(; *s && d < e ;s++) {
- char c = *s;
- if(unlikely(!isprint(c))) c = ' ';
- *d++ = c;
- }
- *d = '\0';
-
- info("Received %zu bytes from graphite backend. Ignoring them. Sample: '%s'", buffer_strlen(b), sample);
- buffer_flush(b);
- return 0;
-}
-
static inline int process_json_response(BUFFER *b) {
- char sample[1024];
- const char *s = buffer_tostring(b);
- char *d = sample, *e = &sample[sizeof(sample) - 1];
-
- for(; *s && d < e ;s++) {
- char c = *s;
- if(unlikely(!isprint(c))) c = ' ';
- *d++ = c;
- }
- *d = '\0';
-
- info("Received %zu bytes from json backend. Ignoring them. Sample: '%s'", buffer_strlen(b), sample);
- buffer_flush(b);
- return 0;
+ return discard_response(b, "json");
}
-static inline int process_opentsdb_response(BUFFER *b) {
- char sample[1024];
- const char *s = buffer_tostring(b);
- char *d = sample, *e = &sample[sizeof(sample) - 1];
-
- for(; *s && d < e ;s++) {
- char c = *s;
- if(unlikely(!isprint(c))) c = ' ';
- *d++ = c;
- }
- *d = '\0';
- info("Received %zu bytes from opentsdb backend. Ignoring them. Sample: '%s'", buffer_strlen(b), sample);
- buffer_flush(b);
- return 0;
-}
+// ----------------------------------------------------------------------------
+// the backend thread
void *backends_main(void *ptr) {
int default_port = 0;
// select the backend type
if(!strcmp(type, "graphite") || !strcmp(type, "graphite:plaintext")) {
+
default_port = 2003;
+ backend_response_checker = process_graphite_response;
+
if(options == BACKEND_SOURCE_DATA_AS_COLLECTED)
backend_request_formatter = format_dimension_collected_graphite_plaintext;
else
backend_request_formatter = format_dimension_stored_graphite_plaintext;
- backend_response_checker = process_graphite_response;
}
else if(!strcmp(type, "opentsdb") || !strcmp(type, "opentsdb:telnet")) {
+
default_port = 4242;
+ backend_response_checker = process_opentsdb_response;
+
if(options == BACKEND_SOURCE_DATA_AS_COLLECTED)
backend_request_formatter = format_dimension_collected_opentsdb_telnet;
else
backend_request_formatter = format_dimension_stored_opentsdb_telnet;
- backend_response_checker = process_opentsdb_response;
}
- else if (!strcmp(type, "json") || !strcmp(type, "json:plaintext"))
- {
+ else if (!strcmp(type, "json") || !strcmp(type, "json:plaintext")) {
+
default_port = 5448;
+ backend_response_checker = process_json_response;
if (options == BACKEND_SOURCE_DATA_AS_COLLECTED)
- {
backend_request_formatter = format_dimension_collected_json_plaintext;
- }
else
- {
backend_request_formatter = format_dimension_stored_json_plaintext;
- }
- backend_response_checker = process_json_response;
}
else {
error("Unknown backend type '%s'", type);