I just don't understand completely all the design thoughts behind the lease
time idea. I've read the conversations here, but still its not all clear.

https://issues.apache.org/jira/browse/OAK-3424
https://issues.apache.org/jira/browse/OAK-3449
https://issues.apache.org/jira/browse/OAK-2739

I'm hardly trying to understand whats going on from the source code. 😑😥

On Sun, Aug 6, 2017 at 11:38 AM, Mostafa Mahdieh <m.mahd...@gmail.com>
wrote:

> Thanks for your suggestions.
>
> I'm wondering what happens in the worst case if I disable the lease check.
>
> In case multiple instances of jackrabbit are run using the same clusterId,
> what are the consequences? Is this all related to logging issues or does it
> have any worse consequences?
>
> On Wed, Aug 2, 2017 at 1:54 PM, Stefan Egli <stefane...@apache.org> wrote:
>
>> Hi Mostafa,
>>
>> I'd suggest to narrow down why that lease update failed, esp if you have
>> it reproducible. By default a lease is updated every 10 seconds and is
>> valid for 2min (and could in theory be changed but that's not recommended
>> necessarily).
>>
>> Besides mentioned DB issues, other cases where lease updates failed were
>> JVMs running low on memory thus doing too long GC-stop-the-worlds.
>>
>> If you can rule out both, then here's some more ideas to investigate:
>>
>> a) check for warnings in the form of: "BackgroundLeaseUpdate.execute:
>> time
>> since last renewClusterIdLease() call longer than expected" to see if the
>> lease update became slow already before it finally expired. Perhaps that
>> gives some clues already.
>>
>> b) enable trace logging for
>> 'org.apache.jackrabbit.oak.plugins.document.ClusterNodeInfo' to see all
>> details about lease updates happening (or not).
>>
>> c) analyse thread dumps to rule out blocked lease update thread
>>
>> Cheers,
>> Stefan
>>
>> On 01/08/17 15:45, "Mostafa Mahdieh" <m.mahd...@gmail.com> wrote:
>>
>> >Hi,
>> >
>> >I'm using jackrabbit oak as the content repository of a document
>> >management
>> >system product. Currently there is no need to scale out, therefore I'm
>> >using jackrabbit oak in a single node environment. However, I'm
>> >experiencing issues related to clustering and lease time, such as the
>> >following exception which is appearing all over my tomcat logs:
>> >
>> >WARN: Background operation failed:
>> >org.apache.jackrabbit.oak.plugins.document.DocumentStoreException: This
>> >oak
>> >instance failed to update the lease in time and can therefore no longer
>> >access this DocumentNodeStore.
>> >
>> >After some research, It seems that there is no way to use jackrabbit oak
>> >forcing it to use a single node and not having any concerns related to
>> >clustering.
>> >
>> >Am I using the right tool? I thought maybe jackrabbit 2 might be better
>> >for
>> >my current use case, however oak seemed as the future of jackrabbit, and
>> >attracted me (adding scalability is also in my future vision). Do you
>> >suggest oak for my usecase or jackrabbit 2? How can I adapt oak for a
>> >single node environment without getting issues regarding lease time and
>> >clustering?
>> >
>> >Best Regards
>> >--
>> >Mostafa Mahdieh
>>
>>
>>
>
>
> --
> Mostafa Mahdieh
>



-- 
Mostafa Mahdieh

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