Tracer Memory Leak

[isaaczinda]

LightStep version 4.2.0, OS X

[feel free to move this to OpenTracing Python if necessary]

I've constructed a minimal reproduction of the issue here. When send_spans_memory_leak is called repeatedly, the program has a memory leak (see graph below). When send_spans_stable is called repeatedly, the program memory footprint is stable.

Although the code in send_spans_memory_leak is illogical (it never actually ends the scope), I can imagine end users writing code like this by mistake. Nevertheless, I think that incorrectly instrumenting an application shouldn't chew up this much memory.

import lightstep

def send_spans_memory_leak(tracer):
    with tracer.start_span(operation_name='make_some_request') as client_span:
        tracer.scope_manager.activate(client_span, True)
        pass

def send_spans_stable(tracer):
    with tracer.start_active_span(operation_name='make_some_request') as client_span:
        pass

# setup tracer
tracer = lightstep.Tracer(
    component_name='isaac_service',
    collector_port=8360,
    collector_host='localhost',
    collector_encryption='none',
    use_http=True,
    access_token='developer',
    max_span_records=100,
)

while True:
    send_spans_memory_leak(tracer)

[isaaczinda]

This is actually an OpenTracing issue so I'm moving this discussion here: opentracing/opentracing-python#125.