unit
Parameters
The units in which the metric value is reported. It is only applicable if the value_type
is INT64
, DOUBLE
, or DISTRIBUTION
. The unit
defines the representation of the stored metric values. Different systems might scale the values to be more easily displayed (so a value of 0.02kBy
might be displayed as 20By
, and a value of 3523kBy
might be displayed as 3.5MBy
). However, if the unit
is kBy
, then the value of the metric is always in thousands of bytes, no matter how it might be displayed. If you want a custom metric to record the exact number of CPU-seconds used by a job, you can create an INT64 CUMULATIVE
metric whose unit
is s{CPU}
(or equivalently 1s{CPU}
or just s
). If the job uses 12,005 CPU-seconds, then the value is written as 12005
. Alternatively, if you want a custom metric to record data in a more granular way, you can create a DOUBLE CUMULATIVE
metric whose unit
is ks{CPU}
, and then write the value 12.005
(which is 12005/1000
), or use Kis{CPU}
and write 11.723
(which is 12005/1024
). The supported units are a subset of The Unified Code for Units of Measure standard: Basic units (UNIT) * bit
bit * By
byte * s
second * min
minute * h
hour * d
day * 1
dimensionless Prefixes (PREFIX) * k
kilo (10^3) * M
mega (10^6) * G
giga (10^9) * T
tera (10^12) * P
peta (10^15) * E
exa (10^18) * Z
zetta (10^21) * Y
yotta (10^24) * m
milli (10^-3) * u
micro (10^-6) * n
nano (10^-9) * p
pico (10^-12) * f
femto (10^-15) * a
atto (10^-18) * z
zepto (10^-21) * y
yocto (10^-24) * Ki
kibi (2^10) * Mi
mebi (2^20) * Gi
gibi (2^30) * Ti
tebi (2^40) * Pi
pebi (2^50) Grammar The grammar also includes these connectors: * /
division or ratio (as an infix operator). For examples, kBy/{email}
or MiBy/10ms
(although you should almost never have /s
in a metric unit
; rates should always be computed at query time from the underlying cumulative or delta value). * .
multiplication or composition (as an infix operator). For examples, GBy.d
or k{watt}.h
. The grammar for a unit is as follows: Expression = Component { "." Component } { "/" Component } ; Component = ( PREFIX UNIT | "%" ) Annotation | Annotation | "1" ; Annotation = "{" NAME "}" ; Notes: * Annotation
is just a comment if it follows a UNIT
. If the annotation is used alone, then the unit is equivalent to 1
. For examples, {request}/s == 1/s
, By{transmitted}/s == By/s
. * NAME
is a sequence of non-blank printable ASCII characters not containing {
or }
. * 1
represents a unitary dimensionless unit of 1, such as in 1/s
. It is typically used when none of the basic units are appropriate. For example, "new users per day" can be represented as 1/d
or {new-users}/d
(and a metric value 5
would mean "5 new users). Alternatively, "thousands of page views per day" would be represented as 1000/d
or k1/d
or k{page_views}/d
(and a metric value of 5.3
would mean "5300 page views per day"). * %
represents dimensionless value of 1/100, and annotates values giving a percentage (so the metric values are typically in the range of 0..100, and a metric value 3
means "3 percent"). * 10^2.%
indicates a metric contains a ratio, typically in the range 0..1, that will be multiplied by 100 and displayed as a percentage (so a metric value 0.03
means "3 percent").