javac server: No port file values materialized. on AIX

[Volker Simonis]

On Mon, Jan 18, 2016 at 8:35 AM, David Holmes <david.holmes at oracle.com> wrote:
> On 18/01/2016 3:08 AM, Andreas Lundblad wrote:
>>
>> On Fri, Jan 15, 2016 at 10:59:08AM +0100, Volker Simonis wrote:
>>>
>>> Maybe the timeout of five seconds is too small?
>>>
>>> Our AIX boxes are not the fastest and we also have a lot of stuff on NFS
>>> shares.
>>>
>>> I recently saw this one:
>>>
>>> [CLIENT] Exception caught: java.io.IOException: No port file values
>>> materialized. Giving up after 6676 ms
>>>
>>> Normally the timeout should be just about a little more than 5 seconds
>>> but here the exception reports more than 6 seconds which might be a
>>> hint that the machine was severely overloaded.
>>>
>>> Regards,
>>> Volker
>>
>>
>> Interesting observation. The code for waiting for valid port file values
>> basically looks like
>>
>>      for (int i = 0; i < 10; i++) {
>>          checkPortFile();
>>          if (successful)
>>              break;
>>          sleep(500);
>>      }
>>
>> so the fact that it even reaches 6676 ms looks suspicious when it comes to
>> load.
>
>
> Why? Under load those sleep(500)'s might not return for much longer; and the
> whole things might be time preempted at any point for an extended period of
> time.

Yes, exactly.

What about putting another loop around this loop which prints a
warning to stdout (e.g. "..trying to connect to sjavac server since X
seconds") for another five or so times. We could also print the system
load [1] although I'm not sure it's worth it. On our AIX machines it
is often a network/NFS problem which causes long startup times of new
executables and this won't be observable by looking at the system load
(but it may at least give a hint').

[1] http://docs.oracle.com/javase/6/docs/api/java/lang/management/OperatingSystemMXBean.html#getSystemLoadAverage%28%29

>
> David
> -----
>
>
>> -- Andreas
>>
>