Re: [Sqlrelay-discussion] getting stuck (Oracle)

[John K. <kl...@gm...>]

I decided to try running just one instance of SQL Relay (rather than
two, with one simply routing SELECTs to the other).  It seems to work
now, so I suspect the issue was that the two instances were stepping
on each other somehow.  I'm still digging...

On Feb 11, 2008 3:29 PM, John Klassa <kl...@gm...> wrote:
> A previous thread on this list suggested that the listener(s) might
> not be running...  They are.  For them, the last debug/log line reads:
>
> 02/11/2008 11:09:25 PST listener [7683] : waiting for client connection...
>
> Thanks.
>
>
> On Feb 11, 2008 12:55 PM, John Klassa <kl...@gm...> wrote:
> > Slight correction...  Clients can occasionally connect, and do a bit
> > more work.  Perhaps something eventually times out and gives up?
> > Regardless, most of the time, clients are just stuck, waiting, and the
> > debug output looks largely the same (i.e. most of them ending in,
> > "acquiring announce mutex").
> >
> >
> > On Feb 11, 2008 12:51 PM, John Klassa <kl...@gm...> wrote:
> > > I have a setup with two SQL Relay instances -- one just routes
> > > "select" statements to the other, and drops anything else.  The
> > > "other" is actually connected to the database, and does work.
> > >
> > > I've found that if I change the worker (the one that's actually
> > > connected to the DB) from having:
> > >
> > >             connections="10"
> > >             maxconnections="10"
> > >
> > > to having :
> > >
> > >             connections="15"
> > >             maxconnections="15"
> > >
> > > then after I run just a few commands through SQL Relay, it hangs.
> > > Clients can't connect, and no work gets done -- even though the SQL
> > > Relay server and the database are sitting largely idle, doing nothing.
> > >  No error messages anywhere (other than timeouts on the clients).
> > > Nothing ever frees up, and SQL Relay never does useful work again,
> > > until I restart it.
> > >
> > > The database user I'm connecting as has no simultaneous session limit,
> > > according to my DBA.  So, I'm at a bit of a loss.  It's as though
> > > something is getting locked, and blocking everything from then on.
> > >
> > > When I turn on debug, the connection debug files end like this (this
> > > is the output of "tail -2" on each):
> > >
> > > 02/11/2008 09:44:15 PST connection [7638] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:43:35 PST connection [7640] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:11 PST connection [7642] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:24 PST connection [7644] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:14 PST connection [7646] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:13 PST connection [7648] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7650] :     waiting for listener
> > >
> > > 02/11/2008 09:44:15 PST connection [7652] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:43:43 PST connection [7661] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:11 PST connection [7663] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:10 PST connection [7665] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7667] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:13 PST connection [7669] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:17 PST connection [7671] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7673] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7685] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:12 PST connection [7687] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:14 PST connection [7689] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:19 PST connection [7691] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:13 PST connection [7693] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:13 PST connection [7699] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:14 PST connection [7701] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7703] :     waiting for listener
> > >
> > > 02/11/2008 09:44:16 PST connection [7708] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:17 PST connection [7710] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7712] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:14 PST connection [7732] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:10 PST connection [7737] :     acquiring announce mutex
> > >
> > > 02/11/2008 09:44:18 PST connection [7744] :
> > > preparing/executing...
> > >
> > > 02/11/2008 09:44:12 PST connection [7753] :     acquiring announce mutex
> > >
> > > So it looks like they're all waiting to acquire the announce mutex.
> > >
> > > I tried building against Oracle 9 and Oracle 10, and get this same
> > > result either way.
> > >
> > > (On that note, I need to post separately about Oracle 10.  I had to
> > > finagle it to build, there.)
> > >
> > > Anyway, any thoughts on how to fix this "announce mutex" issue?
> > >
> > > Thanks!
> > >
> >
>