Hello!

I am using it on FreeBSD systems for moving PostgreSQL databases between
servers with minimum downtime, all works fine.
But when I try to setup permanent master-slave schema some problems  
occured.
Some times (accidentally) master system didn't generate sync events,  
and shutting down
slon on master systems had long time.
After debugging session, i found cause of problem (there is two  
problem, Slony and FreeBSD too).
IMHO there is a logical mistake in slon/scheduler.c, in sched_mainloop  
fdsets copied
for select before checking connections for their timeouts. In timeout  
case this
descriptors will be removed with DLLIST_REMOVE and sched_remove_fdset,  
but stayed in
select descriptors bit vector.
There is a race condition: scheduler and libpq client polls same file  
descriptor and sometime
scheduler select discover readable descriptor and lipbq poll blocks  
for infinte time :(
I tested this on FreeBSD 7.0, trouble repeated in ~60% runs.
I attach a patch, please, take a look on this code, it seems right,  
imho...

Thank you, advance!


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-- 
Cheers,
Oleg A. Mamontov

mailto:  oleg at mamontov.net

icq uin: 79-521-617
cell:    +7-903-798-1352

-- 
Cheers,
Oleg A. Mamontov

mailto:  oleg at mamontov.net

icq uin: 79-521-617
cell:    +7-903-798-1352