Connection hangs when truncating a transaction by bringing down the server - ATS 7.1.3

[suprajasridhar]

ATS 7.1.3 with bnull-transaform plugin hangs when server aborts a transaction.

Last few log lines before ATS hangs in this state

[Sep 17 14:50:53.999] Server {0x2ba8c98be700} DEBUG: <HttpSM.cc:3053 (tunnel_handler_server)> (http) [0] [HttpSM::tunnel_handler_server] aborting HTTP tunnel due to server truncation
[Sep 17 14:50:53.999] Server {0x2ba8c98be700} DEBUG: <HttpServerSession.cc:125 (do_io_close)> (http_ss) [0] session closing, netvc 0x2ba90c018800
[Sep 17 14:50:53.999] Server {0x2ba8c98be700} DEBUG: <HttpSM.cc:2679 (main_handler)> (http) [0] [HttpSM::main_handler, HTTP_TUNNEL_EVENT_DONE]
[Sep 17 14:50:53.999] Server {0x2ba8c98be700} DEBUG: <HttpSM.cc:1246 (state_response_wait_for_transform_read)> (http) [0] [&HttpSM::state_response_wait_for_transform_read, HTTP_TUNNEL_EVENT_DONE]
[Sep 17 14:50:53.999] Server {0x2ba8c98be700} DEBUG: <HttpSM.cc:1276 (state_common_wait_for_transform_read)> (http) [0] [&HttpSM::state_common_wait_for_transform_read, HTTP_TUNNEL_EVENT_DONE]

[nqyy]

When I tested it, I found out null-transform doesn't have such issue, wondering the difference between them.

[suprajasridhar]

I believe null-tranform writes out immediately after it gets response. Buffered null transform waits for the entire response before writing back. ATS hangs when the response doesn't even begin to come out of the transform.

[suprajasridhar]

I found this commit relevant to the issue I am facing. e6b9cb5.
If I replace tunnel.chain_abort_all with tunnel.abort_cache_write_finish_others the connection seems to close.

[nqyy]

Which tunnel.chain_abort_all did you replace?

[suprajasridhar]

Line:2843

[bryancall]

@willwendorfvm can you please take a look at this