[99s-extend] Cowboy unexpectedly timing out when reading the body

[Phillips, Christopher]

On a dev server I had a Cowboy app suddenly start returning timeouts when calling cowboy_req:body_qs(Request), with surprising frequency, which in turn led to 500s back to the calling client. It only appeared to happen when hitting one particular resource, and was sporadic, and I was wondering if there might be some explanation related to Cowboy (as opposed to maybe really weird VM issues). For full disclosure, we would first check the body with cowboy_req:body(Request) as part of an access log, then ignore the returned cowboy_req:req() that call passed back, since we could not then stream the body off of it again. It was working fine, so I don't think it was related, but it seems more solid now after I removed it and I don't know if that's related or not.



Here is an example request that dumped when the process died -


{req,[{socket,#Port<0.7113>},{transport,ranch_tcp},{connection,keepalive},{pid,<0.1805.0>},{method,<<"POST">>},{version,'HTTP/1.1'},{peer,{{10,188,32,225},53188}},{host,<<"bps-feedschedulervip1.turner.com">>},{host_info,undefined},{port,8091},{path,<<"/encoders/Player1/record">>},{path_info,[<<"record">>]},{qs,<<"authToken=...">>},{qs_vals,[{<<"authToken">>,<<"...">>}]},{bindings,[{id,<<"Player1">>}]},{headers,[{<<"host">>,<<"bps-feedschedulervip1.turner.com:8091">>},{<<"content-type">>,<<"application/x-www-form-urlencoded; charset=UTF-8">>},{<<"origin">>,<<"http://bps-newstrondev1.turner.com">>},{<<"content-length">>,<<"48">>},{<<"connection">>,<<"keep-alive">>},{<<"accept">>,<<"application/json, text/javascript, */*; q=0.01">>},{<<"user-agent">>,<<"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_2) AppleWebKit/537.74.9 (KHTML, like Gecko) Version/7.0.2 Safari/537.74.9">>},{<<"referer">>,<<"http://bps-newstrondev1.turner.com/newstron/record/record.html">>},{<<"accept-language">>,<<"en-us">>},{<<"accept-encoding">>,<<"gzip, deflate">>}]},{p_headers,[{<<"content-type">>,{<<"application">>,<<"x-www-form-urlencoded">>,[{<<"charset">>,<<"utf-8">>}]}},{<<"if-modified-since">>,undefined},{<<"if-none-match">>,undefined},{<<"if-unmodified-since">>,undefined},{<<"if-match">>,undefined},{<<"accept">>,[{{<<"application">>,<<"json">>,[]},1000,[]},{{<<"text">>,<<"javascript">>,[]},1000,[]},{{<<"*">>,<<"*">>,[]},10,[]}]},{<<"connection">>,[<<"keep-alive">>]}]},{cookies,undefined},{meta,[{charset,undefined},{media_type,{<<"application">>,<<"json">>,[]}}]},{body_state,waiting},{multipart,undefined},{buffer,<<>>},{resp_compress,false},{resp_state,waiting},{resp_headers,[{<<"content-type">>,[<<"application">>,<<"/">>,<<"json">>,<<>>]},{<<"Access-Control-Allow-Origin">>,<<"*">>}]},{resp_body,<<>>},{onresponse,#Fun<access_log_responder.onresponse.4>}]}




As I said, it may be just due to VM issues or something, but I figured I'd ask in case there was any obvious issue.
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