tree 790292d11814ae16ddfd94a0e40c8481ecfe4a39
parent 4710d207432c8f7b937707176e512a2a709cf55c
author Christopher Faulet <cfaulet@haproxy.com> 1546529094 +0100
committer Willy Tarreau <w@1wt.eu> 1546537500 +0100
encoding latin1

BUG/MAJOR: stream-int: Update the stream expiration date in stream_int_notify()

Since a long time, the expiration date of a stream is only updated in
process_stream(). It is calculated, among others, using the channels expiration
dates for reads and writes (.rex and .wex values). But these values are updated
by the stream-interface. So when this happens at the connection layer, the
update is only done if the stream's task is woken up. Otherwise, the stream
expiration date is not immediatly updated. This leads to unexpected
behaviours. Time to time, users reported that the wrong timeout was hitted or
the wrong termination state was reported. This is partly because of this
bug.

Recently, we observed some blocked sessions for a while when big objects are
served from the cache applet. It seems only concern the clients not reading the
response. Because delivered objects are big, not all data can be sent. And
because delivered objects are big, data are fast forwarded (from the input to
the output with no stream wakeup). So in such situation, the stream expiration
date is never updated and no timeout is hitted. The session remains blocked
while the client remains connected.

This bug exists at least since HAProxy 1.5. But recent changes on the connection
layer make it more visible. It must be backported from 1.9 to 1.6. And with more
pain it should be backported to 1.5.