[omniORB] omniORB, posix rwlock_t and deadlock

[Duncan Grisby]

On Tuesday 12 June, Attila Pletyak wrote:

[...]
>    Does anyone has experience with such a thing? Is there an omniORB 
> specific thread synchronization tool which works like the rwlock? 
> Previously I used the omni_mutex, but it was slow as in the base class 
> there is only reading in the majority of the time.

omniORB doesn't hold any locks when it makes an up-call into
application code (unless you are using a single thread policy POA), so
I doubt it can be the direct cause of your deadlock.

A good thing to help track down the deadlock is to attach to the
frozen process with gdb and do a backtrace on each of the threads. If
it really is deadlocked, you'll see at least two threads blocked
attempting to acquire different resources.

On the subject of a reader-writer lock based on omnithread, look at
src/appl/omniNames/ReadersWritersLock.h. That file is licensed under
GPL, but if that causes a problem for you I'm sure you can use it as
inspiration for your own implementation :-).

Cheers,

Duncan.

-- 
 -- Duncan Grisby  \  Research Engineer  --
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