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From Cameron McKenzie <mckenzie....@gmail.com>
Subject Re: cache recipes
Date Thu, 17 Nov 2016 22:58:31 GMT
Hey Scott,
This would mean blocking the main thread until the event arrives though yes?

I think that Hendrik was taking about having the cache updated as soon as
the write is acknowledged by ZK, rather than waiting for the watcher to
fire.

On 18 Nov 2016 9:47 AM, "Scott Blum" <dragonsinth@gmail.com> wrote:

> You can also just listen for TreeCache events and wait for your change to
> come through.
>
> On Thu, Nov 17, 2016 at 3:18 PM, Hendrik Haddorp <hendrik.haddorp@gmx.net>
> wrote:
>
>> Thanks, that was a pretty fast answer! Not quite what I had hoped for but
>> at least now I know that I was right that I have to handle this myself :-)
>>
>>
>> On 17.11.2016 21:13, Cameron McKenzie wrote:
>>
>> Hey Hendrick,
>> The recipes don't treat local updates any differently to remote updates.
>> The cache will get updated when the cursor client receives a watch event
>> from Zookeeper.
>>
>> So your assertions are correct. The caches provide eventual consistency.
>> If you need to ensure that there are no dirty reads between when you write
>> locally and when you read from the cache you would need to wrap the cache
>> in some manner.
>>
>> Cheers
>>
>> On 18 Nov 2016 7:06 AM, "Hendrik Haddorp" <hendrik.haddorp@gmx.net>
>> wrote:
>>
>>> Hi,
>>>
>>> I'm trying to use a cache recipe, like the TreeCache. The cache itself
>>> works just fine but what I don't understand is how I'm supposed to handle
>>> locally triggered updates correctly. I can start the TreeCache and using
>>> the events I know when it is initialized but what if I delete a child node
>>> or update a node for example? If I read the data out of the cache before I
>>> get the corresponding update events I get old data. As there doesn't seem
>>> to be an invalidation mechanism I seem to be required to track outstanding
>>> updates. Or am I missing something?
>>>
>>> regards,
>>> Hendrik
>>>
>>
>>
>

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