register collector with error duplicate metrics collector registration attempted

[qianfangyuan]

register with collector with error duplicate metrics collector registration attempted

prometheus save collector with a uint64 number with key, and collector as value
collectorsByID map[uint64]Collector // ID is a hash of the descIDs.
the number is calculate with each ConstLabels and fqName and add that all:

func fq(labelValues[]string)uint64{
vh := hashNew()
for _, val := range labelValues {
vh = hashAdd(vh, val)
vh = hashAddByte(vh, separatorByte)
}
return vh

}

const (
offset64 = 14695981039346656037
prime64 = 1099511628211
)
const separatorByte byte = 255

// hashNew initializies a new fnv64a hash value.
func hashNew() uint64 {
return offset64
}

// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
func hashAdd(h uint64, s string) uint64 {
for i := 0; i < len(s); i++ {
h ^= uint64(s[i])
h *= prime64
}
return h
}

// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
func hashAddByte(h uint64, b byte) uint64 {
h ^= uint64(b)
h *= prime64
return h
}

when two collectors have the same fqName and different ConstLabels
collectorA:
labelValues1=[]string{"mysql_exporter_scrapes_total","3411"}
labelValues2=[]string{"mysql_exporter_scrape_errors_total","3411"}
labelValues3=[]string{"mysql_exporter_last_scrape_error","3411"}
labelValues4=[]string{"mysql_up","3411"}
cal:
9288655250343904629+16028598718722608554+9509180690289043793+5153831169212418182-18446744073709551615*2=3086777681148871926

collectorB:
labelValues1=[]string{"mysql_exporter_scrapes_total","3413"}
labelValues2=[]string{"mysql_exporter_scrape_errors_total","3413"}
labelValues3=[]string{"mysql_exporter_last_scrape_error","3413"}
labelValues4=[]string{"mysql_up","3413"}
cal:
9290907050158102307+16026346918908410876+9510869540149597439+5152142319351864536-18446744073709551615*2=3086777681148871926
but have the same cal id:3086777681148871926

with different constLabels but cal the same collectorID,so register failed

[brian-brazil]

It makes more sense to ask questions like this on the prometheus-users mailing list rather than in a GitHub issue. On the mailing list, more people are available to potentially respond to your question, and the whole community can benefit from the answers provided.