[Quickfix-developers] Gap Fills blocking?

[John H. <jh...@ca...>]

Oren,

A long time ago a thread went around this mailing list discussing the
Gap Fill process as it relates to the threaded socket initiators and
acceptors.  The issue was essentially that QF would block other
threads during a Gap Fill request on a session managed by the threaded
acceptor.  I believe that at the time somebody had submitted a fix to
this issue -- but I can't say with certainty.

Do you happen to know if the 1.13.x build(s) have addressed this
issue, or if I should still expect 1.13.x to behave the same way?

[If the above makes sense, please read no further.  If I've lost you,
please read on for an example of what I've been seeing...]

Suppose I have a FIX message gateway app (using QF 1.12.4
out-of-the-box, pre-built DLLs in .NET) which creates a threaded
initiator with a session out to ARCA, and which creates a threaded
acceptor with three sessions from Client #1, Client #2 and Client #3.
When my gateway gets a message from ARCA, it sends a copy to each
Client so that all three clients see each other's order acks+fills.

Now suppose Client #1 and Client #2 connect to their session in the
morning, while Client #3 is disconnected.  A message queue builds up
in QF (because of the traffic from Clients #1 and #2) waiting for
Client #3 to connect.  After lunch Client #3 connects and there are
100,000+ messages waiting to flow from the gateway down to Client #3.
While QF performs the Gap Fill of these 100,000+ messages, all message
traffic from ARCA is blocked -- sessions for Clients #1 and #2 do not
receive messages coming from ARCA, and QF won't respond to ARCA's Test
Requests - while the queue'd message are passed down to Client #3.

I'm curious if this was addressed in the latest build(s) or if I
should expect the same behavior if I migrate up from 1.12.4.

Many thanks,

  John