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Pig >> mail # user >> Regarding Eval UDF in pig 0.9.1


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Re: Regarding Eval UDF in pig 0.9.1
Pig does not use multiple threads for executing the udf (at least in
versions so far, and i haven't seen any proposals to change that).
So you don't need to deal with synchronization issues. But if you are
using a static variables, remember that there can be multiple instances
of the udf - one for each place in the pig-latin script where you use
the udf.

-Thejas
On 12/20/11 3:32 PM, Rohini U wrote:
> Hi,
>
> I am using a static HashMap in EvalUDF which needs configuration, so I am
> initializing it in exec method checking if it is null
>
>
>      @Override
>      public String exec(Tuple input) throws IOException {
>                if(dict== null){
>
> dict=MyDictionary.getInstance(UDFContext.getUDFContext().getJobConf());
>           }
>      // Other piece of code here
>
>     }
>
> Now, in the getInstance method, do I have to take care of any thread
> synchronization issues? Is there a chance that multiple threads access it?
>
> Thanks,
> -Rohini
>