This is an unsupported open source project created by DataStax employees.
Hunter performs statistical analysis of performance test results stored in CSV files or Graphite database. It finds change-points and notifies about possible performance regressions.
A typical use-case of hunter is as follows:
- A set of performance tests is scheduled repeatedly.
- The resulting metrics of the test runs are stored in a time series database (Graphite) or appended to CSV files.
- Hunter is launched by a Jenkins/Cron job (or an operator) to analyze the recorded metrics regularly.
- Hunter notifies about significant changes in recorded metrics by outputting text reports or sending Slack notifications.
Hunter is capable of finding even small, but systematic shifts in metric values,
despite noise in data.
It adapts automatically to the level of noise in data and tries not to notify about changes that
can happen by random. Unlike in threshold-based performance monitoring systems,
there is no need to setup fixed warning threshold levels manually for each recorded metric.
The level of accepted probability of false-positives, as well as the
minimal accepted magnitude of changes are tunable. Hunter is also capable of comparing
the level of performance recorded in two different periods of time – which is useful for
e.g. validating the performance of the release candidate vs the previous release of your product.
This is still work-in-progress, unstable code. Features may be missing. Usability may be unsatisfactory. Documentation may be incomplete. Backward compatibility may be broken any time.
See CONTRIBUTING.md for development instructions.
Hunter requires Python 3.8. If you don't have python 3.8, use pyenv to install it.
Use pipx to install hunter:
pipx install git+ssh://git@github.com/datastax/hunter
Copy the main configuration file resources/hunter.yaml
to ~/.hunter/hunter.yaml
and adjust
Graphite and Grafana addresses and credentials.
Alternatively, it is possible to leave the config file as is, and provide credentials in the environment by setting appropriate environment variables. Environment variables are interpolated before interpreting the configuration file.
All test configurations are defined in the main configuration file. Currently, there are two types of tests supported: tests that publish their results to a CSV file, and tests that publish their results to a Graphite database.
Tests are defined in the tests
section.
The following definition will import results of the test from a local CSV file:
tests:
local.sample:
type: csv
file: tests/resources/sample.csv
time_column: time
metrics: [metric1, metric2]
attributes: [commit]
csv_options:
delimiter: ","
quote_char: "'"
The time_column
property points to the name of the column storing the timestamp
of each test-run. The data points will be ordered by that column.
The metrics
property selects the columns tha hold the values to be analyzed. These values must
be numbers convertible to floats. The metrics
property can be not only a simple list of column
names, but it can also be a dictionary configuring other properties of each metric,
the column name or direction:
metrics:
resp_time_p99:
direction: -1
column: p99
Direction can be 1 or -1. If direction is set to 1, this means that the higher the metric, the better the performance is. If it is set to -1, higher values mean worse performance.
The attributes
property describes any other columns that should be attached to the final
report. Special attribute version
and commit
can be used to query for a given time-range.
To import data from Graphite, the test configuration must inform Hunter how the data are published in your history server. This is done by specifying the Graphite path prefix common for all the test's metrics and suffixes for each of the metrics recorded by the test run.
tests:
my-product.test:
type: graphite
tags: [perf-test, daily, my-product]
prefix: performance-tests.daily.my-product
metrics:
throughput:
suffix: client.throughput
response-time:
suffix: client.p50
direction: -1 # lower is better
cpu-load:
suffix: server.cpu
direction: -1 # lower is better
The optional tags
property contains the tags that are used to query for Graphite events that store
additional test run metadata such as run identifier, commit, branch and product version information.
The following command will post an event with the test run metadata:
$ curl -X POST "http://graphite_address/events/" \
-d '{
"what": "Performance Test",
"tags": ["perf-test", "daily", "my-product"],
"when": 1537884100,
"data": {"commit": "fe6583ab", "branch": "new-feature", "version": "0.0.1"}
}'
Posting those events is not mandatory, but when they are available, Hunter is able to
filter data by commit or version using --since-commit
or --since-version
selectors.
You may find that your test definitions are very similar to each other, e.g. they all have the same metrics. Instead of copy-pasting the definitions you can use templating capability built-in hunter to define the common bits of configs separately.
First, extract the common pieces to the templates
section:
templates:
common-metrics:
throughput:
suffix: client.throughput
response-time:
suffix: client.p50
direction: -1 # lower is better
cpu-load:
suffix: server.cpu
direction: -1 # lower is better
Next you can recall a template in the inherit
property of the test:
my-product.test-1:
type: graphite
tags: [perf-test, daily, my-product, test-1]
prefix: performance-tests.daily.my-product.test-1
inherit: common-metrics
my-product.test-2:
type: graphite
tags: [perf-test, daily, my-product, test-2]
prefix: performance-tests.daily.my-product.test-2
inherit: common-metrics
You can inherit more than one template.
hunter list-groups
hunter list-tests [group name]
To list all available metrics defined for the test:
hunter list-metrics <test>
hunter analyze <test>...
hunter analyze <group>...
This command prints interesting results of all
runs of the test and a list of change-points.
A change-point is a moment when a metric value starts to differ significantly
from the values of the earlier runs and when the difference
is consistent enough that it is unlikely to happen by chance.
Hunter calculates the probability (P-value) that the change point was caused
by chance - the closer to zero, the more "sure" it is about the regression or
performance improvement. The smaller is the actual magnitude of the change,
the more data points are needed to confirm the change, therefore Hunter may
not notice the regression after the first run that regressed.
The analyze
command accepts multiple tests or test groups.
The results are simply concatenated.
$ hunter analyze local.sample
INFO: Computing change points for test sample.csv...
sample:
time metric1 metric2
------------------------- --------- ---------
2021-01-01 02:00:00 +0000 154023 10.43
2021-01-02 02:00:00 +0000 138455 10.23
2021-01-03 02:00:00 +0000 143112 10.29
2021-01-04 02:00:00 +0000 149190 10.91
2021-01-05 02:00:00 +0000 132098 10.34
2021-01-06 02:00:00 +0000 151344 10.69
·········
-12.9%
·········
2021-01-07 02:00:00 +0000 155145 9.23
2021-01-08 02:00:00 +0000 148889 9.11
2021-01-09 02:00:00 +0000 149466 9.13
2021-01-10 02:00:00 +0000 148209 9.03
Change points found by analyze
can be exported
as Grafana annotations using the --update-grafana
flag:
$ hunter analyze <test or group> --update-grafana
The annotations generated by Hunter get the following tags:
hunter
change-point
test:<test name>
metric:<metric name>
- tags configured in the
tags
property of the test - tags configured in the
annotate
property of the test - tags configured in the
annotate
property of the metric
Additionally, the annotate
property supports variable tags:
%{TEST_NAME}
- name of the test%{METRIC_NAME}
- name of the metric%{GRAPHITE_PATH}
- resolves to the path to the data in Graphite%{GRAPHITE_PATH_COMPONENTS}
- splits the path of the data in Graphite into separate components and each path component is exported as a separate tag%{GRAPHITE_PREFIX}
- resolves to the prefix of the path to the data in Graphite (the part of the path up to the metric suffix)%{GRAPHITE_PREFIX_COMPONENTS}
- similar as%{GRAPHITE_PATH_COMPONENTS}
but splits the prefix of the path instead of the path
Often we want to know if the most recent product version
performs at least as well as one of the previous releases. It is hard to tell that by looking
at the individual change points. Therefore, Hunter provides a separate command for comparing
the current performance with the baseline performance level denoted by --since-XXX
selector:
$ hunter regressions <test or group>
$ hunter regressions <test or group> --since <date>
$ hunter regressions <test or group> --since-version <version>
$ hunter regressions <test or group> --since-commit <commit>
If there are no regressions found in any of the tests,
Hunter prints No regressions found
message.
Otherwise, it gives a list of tests with metrics and
magnitude of regressions.
In this test, Hunter compares performance level around the baseline ("since") point with the performance level at the end of the time series. If the baseline point is not specified, the beginning of the time series is assumed. The "performance level at the point" is computed from all the data points between two nearest change points. Then two such selected fragments are compared using Student's T-test for statistical differences.
$ hunter regressions local.sample
INFO: Computing change points for test local.sample...
local.sample:
metric2 : 10.5 --> 9.12 ( -12.9%)
Regressions in 1 test found
$ hunter regressions local.sample --since '2021-01-07 02:00:00'
INFO: Computing change points for test local.sample...
local.sample: OK
No regressions found!
The hunter regressions
command can work with feature branches.
First you need to tell Hunter how to fetch the data of the tests run against a feature branch.
The prefix
property of the graphite test definition accepts %{BRANCH}
variable,
which is substituted at the data import time by the branch name passed to --branch
command argument. Alternatively, if the prefix for the main branch of your product is different
from the prefix used for feature branches, you can define an additional branch_prefix
property.
my-product.test-1:
type: graphite
tags: [perf-test, daily, my-product, test-1]
prefix: performance-tests.daily.%{BRANCH}.my-product.test-1
inherit: common-metrics
my-product.test-2:
type: graphite
tags: [perf-test, daily, my-product, test-2]
prefix: performance-tests.daily.master.my-product.test-2
branch_prefix: performance-tests.feature.%{BRANCH}.my-product.test-2
inherit: common-metrics
Now you can verify if correct data are imported by running
hunter analyze <test> --branch <branch>
.
The --branch
argument also works with hunter regressions
. In this case a comparison will be made
between the tail of the specified branch and the tail of the main branch (or a point of the
main branch specified by one of the --since
selectors).
$ hunter regressions <test or group> --branch <branch>
$ hunter regressions <test or group> --branch <branch> --since <date>
$ hunter regressions <test or group> --branch <branch> --since-version <version>
$ hunter regressions <test or group> --branch <branch> --since-commit <commit>
Sometimes when working on a feature branch, you may run the tests multiple times,
creating more than one data point. To ignore the previous test results, and compare
only the last few points on the branch with the tail of the main branch,
use the --last <n>
selector. E.g. to check regressions on the last run of the tests
on the feature branch:
$ hunter regressions <test or group> --branch <branch> --last 1
Please beware that performance validation based on a single data point is quite weak and Hunter might miss a regression if the point is not too much different from the baseline.
Copyright 2021 DataStax Inc
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
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