JDK 8 RFR 8010371: getaddrinfo can fail with EAI_SYSTEM/EAGAIN, causes UnknownHostException to be thrown

[Chris Hegarty]

On 10/02/2013 11:18 PM, Dmitry Samersoff wrote:
> Chris,
>
> I'm not sure immediate native retry make sence here because tipically
> EAGAIN of getaddrinfo caused by network failure, like unreachable
> nameserver. (see my previous letter)

OK, while not ideal ( please don't shoot! ) what do others think of 
Thread.yield() before retry. It is an attempt to allow other threads on 
the system do some work before us, therefore potentially swapping out 
our failed lookup thread until rescheduled. I'm just trying to avoid 
baking in a hardcoded sleep/wait value ( since we don't know what that 
should be ).

The use of Thread.yield(), if acceptable, would of course most likely 
make sense to push the retry logic back up into the Java level.

-Chris.

>
> -Dmitry
>
> On 2013-10-02 23:53, Chris Hegarty wrote:
>> On 10/02/2013 08:40 PM, Brian Burkhalter wrote:
>>> ....
>>> So, how about this approach:
>>>
>>> 1) If the error is EAI_AGAIN / EIA_SYSTEM+EAGAIN / WSATRY_AGAIN then
>>> do one immediate native retry.
>>> 2) If the retry fails with the same error, then throw a UHE with a
>>> specific message or cause.
>>
>> Sounds good to me.
>>
>>> Questions:
>>>
>>> A) Would it be better to do the retry in the Java layer, perhaps with
>>> a very short wait?
>>
>> native, without any wait, should be sufficient.
>>
>>> B) Should the message or cause in #2 be explicitly document in the
>>> javadoc?
>>
>> I don't think it is necessary for this to be documented. It is more
>> informational.
>>
>> -Chris.
>
>