oss-fuzz/docs/clusterfuzz.md

# ClusterFuzz

[ClusterFuzz](https://blog.chromium.org/2012/04/fuzzing-for-security.html) is the distributed fuzzing infrastructure behind OSS-Fuzz. It was initially built
for fuzzing Chrome at scale.

## Web interface

ClusterFuzz provides a [web interface](https://oss-fuzz.com)
to view statistics about your fuzz targets, as well as current crashes.

*Note*: Access is restricted to project developers who we auto CC on new bug reports.

## Testcase reports

ClusterFuzz will automatically de-duplicate and file reproducible crashes into
our [bug tracker](https://bugs.chromium.org/p/monorail). We provide a crash
report page that gives you the stack trace, a link to the crashing testcase, and
regression ranges where the bug was most likely introduced.

![report](https://raw.githubusercontent.com/google/oss-fuzz/master/docs/images/pcre2_testcase.png)

## Fuzzer stats

You can view statistics about your fuzz targets (e.g. speed, coverage information,
memory usage) on our fuzzer statistics dashboard.

![stats](https://raw.githubusercontent.com/google/oss-fuzz/master/docs/images/freetype_stats.png)

## Coverage reports

We provide coverage reports, where we highlight the parts of source code that are being
reached by your fuzz target.

![coverage_1](https://raw.githubusercontent.com/google/oss-fuzz/master/docs/images/freetype_coverage_1.png)
![coverage_2](https://raw.githubusercontent.com/google/oss-fuzz/master/docs/images/freetype_coverage_2.png)

## Performance analyzer

You can view performance issues that your fuzz target is running into (e.g. leaks, timeouts, etc) by
clicking on `Performance` link on our fuzzer statistics dashboard.

![performance_analyzer](https://raw.githubusercontent.com/google/oss-fuzz/master/docs/images/expat_performance_analyzer.png)