dupefinder

Produces a report on duplicated heap allocations and likely source locations.

To start, collect a heap snapshot (see http://go/fuchsia-heapdump for details):

ffx profile heapdump snapshot \
    --output-file /path/to/profile.pb \
    --output-contents-dir /path/to/contents \
    --by-name instrumented-process.cm
    --symbolize

Note that the snapshot must be symbolized to get meaningful results from this tool.

Pass the collected snapshot to dupefinder:

fx dupefinder \
    --profile /path/to/symbolized.pb.gz \
    --contents-dir /path/to/contents \
    --html-output /path/to/dupes_report.html

The report has some basic configuration options, see fx dupefinder --help.