[OpenSER-Devel] need advice for avp lock

[Di-Shi Sun]

Hi Henning,

Our case is like this:
1. Our tm call back function was triggered by out 180 and 200. The interval
between 180 and 200 was so short.
2. The call back function accessed a set of AVPs and set a flag (in AVP
value) for every AVP to mark these AVPs were comsumed. This flag made these
AVPs to be used only once. Since the call back function was called twice at
almost the same time, the race condition happned that some AVPs were used
twice.

According the source code, we believe that USE_PTHREAD_MUTEX lock set is
thread safe and can be used for AVP. But the default lock set is FAST_LOCK.
We do not know if it can be used for AVP.

Regards,

Di-Shi Sun.

----- Original Message ----- 
From: "Henning Westerholt" <henning.westerholt at 1und1.de>
To: "Di-Shi Sun" <di-shi at transnexus.com>
Cc: <devel at openser.org>; "Support of TransNexus" <support at transnexus.com>
Sent: Tuesday, October 23, 2007 9:35 PM
Subject: Re: [OpenSER-Devel] need advice for avp lock


> On Thursday 18 October 2007, Di-Shi Sun wrote:
> > Hi Henning,
> >
> > I believe we met the same problem. For us, only one flag in an AVP (5
AVPs
> > for a call) is set and the logic is simple. So, we did not meet a crash
> > condition. It happened 17 times in a 1M call test at 50 cps.
> >
> > Klaus Darilion suggested we read the tm code for the AVP lock. I will
study
> > it.
>
> I've studied this code too, but i found nothing helpful. What kind of
error
> you've observed? In your first mail you spoke about a race condition, is
the
> wrong AVP value accessed?
>
> Cheers,
>
> Henning
>
>