[ovs-dev] [PATCH] ovn-northd: Recalculate db mappings if the txn returns TXN_ERROR

[Ben Pfaff]

On Sun, Dec 13, 2015 at 07:46:52PM +0530, Numan Siddique wrote:
> Fixes the issue
> Reported-at: http://openvswitch.org/pipermail/discuss/2015-November/019443.html
> 
> Signed-off-by: Numan Siddique <nusiddiq at redhat.com>

This patch has been sitting too long without review.  This is my fault.
I apologize.

I'm concerned about this patch for a couple of reasons.  First, the goal
of the ovsdb_idl_loop abstraction is to make it easy for clients to get
all of this stuff right.  This patch adds more code outside the
ovsdb_idl_loop implementation in its client, somewhat reducing the value
of the abstraction.  It would be better if we could instead integrate
the logic into ovsdb_idl_loop itself.

My second concern is larger.  TXN_ERROR is supposed to indicate a hard
error, one for which retrying immediately is not going to help.  What
kind of error did testing actually encounter?  Perhaps the real bug is
that an error is being misclassified as TXN_ERROR.