Since Ethan is out, can you investigate this, Ben?

I tried substituting in systemHealthMetrics as the metric under the battor benchmark, and got:

"""
[ RUN      ] /var/folders/pm/q_gmk1r17pj_rnnc9vv4k7g0003db3/T/tmpJdyYwY.html
MapFunctionError: Cannot read property 'buildFromEvents' of undefined
    at Object.longTasksMetric (/tracing/metrics/system_health/long_tasks_metric.html:93:41)
    at new systemHealthMetrics (/tracing/metrics/system_health/system_health_metrics.html:21:19)
    at runMetrics (/Users/erikchen/projects/chromium/src/third_party/catapult/tracing/tracing/metrics/metric_map_function.html:37:14)
    at metricMapFunction (/Users/erikchen/projects/chromium/src/third_party/catapult/tracing/tracing/metrics/metric_map_function.html:71:18)
    at Object.mapSingleTrace (/tracing/mre/map_single_trace.html:41:7)
    at eval (/Users/erikchen/projects/chromium/src/third_party/catapult/tracing/tracing/mre/map_single_trace_cmdline.html:61:18)
    at Object.runAndConvertErrorsToFailures (/tracing/mre/map_single_trace.html:26:10)
    at mapSingleTraceWithResult (/Users/erikchen/projects/chromium/src/third_party/catapult/tracing/tracing/mre/map_single_trace_cmdline.html:52:12)
    at Object.mapSingleTraceMain (/Users/erikchen/projects/chromium/src/third_party/catapult/tracing/tracing/mre/map_single_trace_cmdline.html:76:18)
    at eval (/Users/erikchen/projects/chromium/src/third_party/catapult/tracing/tracing/mre/map_single_trace_cmdline.html:89:15)
"""

Looks like a lot of this code is never used by benchmarks?

I fixed that. Please rebase.

https://github.com/catapult-project/catapult/commits/master/tracing/tracing/metrics/system_health/long_tasks_metric.html

Sorry, to clarify, I fixed the longTasksMetric bug described in comment 2.

I have not investigated why cpu_time_percentage is empty from telemetry.

Erik: can you try open the results2.html file in TOT chrome? I found out that I had same problem with metric side panel, but only on beta-Chrome

cpuDuration is not guaranteed to be a number on all slices.
https://codereview.chromium.org/2356253005
In lthi_cats, the slice whose title is"RendererMain.START_MSG_LOOP" and category is "ETW Trace Event" has cpuDuration = undefined.

In javascript, any number plus undefined yields NaN.
When cpuTimeMetric calls addSample(NaN), the Histogram says numNans++ but can't increment the count of any bin. There is a summary statistic "nans", but it defaults to off, so the histogram looks totally empty.

erikchen: is this fixed?

yes