Here is a set of functions of the pattern <TIMEPERIOD>_before()
. These functions display the values from the corresponding time period on the graph. On their own, they may not be of high value, but together with the current values they may provide useful insight into the performance of your application.
Timeshift
Function | Description | Example |
---|
timeshift() | Graph values from an arbitrary <TIME_IN_SECOND> before the current timestamp for the metric. | timeshift(<METRIC_NAME>{*}, -<TIME_IN_SECOND>) |
For example, if you wanted to use this to compare current system load with load from 2 weeks ago (60*60*24*14 = 1209600), your query would be:
timeshift(avg:system.load.1{*}, -1209600)
Hour before
Function | Description | Example |
---|
hour_before() | Graph values from an hour before the current timestamp for the metric. | hour_before(<METRIC_NAME>{*}) |
Here is an example of system.load.1
with the hour_before()
value shown as a dotted line. In this particular example, you can see the machine was started at 6:30am and the hour_before()
values show up at the 7:30 mark. Of course, this example was created specifically so that you can see the hour_before()
values match up with the actual values.
Day before
Function | Description | Example |
---|
day_before() | Graph values from a day before the current timestamp for the metric. | day_before(<METRIC_NAME>{*}) |
Here is an example of nginx.net.connections
with the day_before()
value shown as a lighter, thinner line. In this example, you can see a week’s worth of data, which makes the day_before()
data easier to identify.
Week before
Function | Description | Example |
---|
week_before() | Graph values from a week (7 days) before the current timestamp for the metric. | week_before(<METRIC_NAME>{*}) |
Here is an example of cassandra.db.read_count
with the week_before()
value shown as a dotted line. In this example, you can see about three weeks’ worth of data, which makes the week_before()
data easier to identify.
Month before
Function | Description | Example |
---|
month_before() | Graph values from a month (28 days / 4 weeks) before the current timestamp for the metric. | month_before(<METRIC_NAME>{*}) |
Here is an example of aws.ec2.cpuutilization
with the month_before()
value shown as a thin, solid line.
Other functions
Consult the other available functions:
Further Reading
Additional helpful documentation, links, and articles: