Ikai,

Yes you are right the expensive part is initializing
the EntityManagerFactory in my case. Is there any way we can improve
the performance on that.

Thanks,
Rahul
----------------------------------------------------------
Rahul Juneja
http://techlabs.thoughtclicks.com


On Wed, Jun 2, 2010 at 12:55 PM, Ikai L (Google) <[email protected]> wrote:

> There's very little cost to "connecting" to the datastore. If this is an
> issue, I'd look at the low-level API for anything that could be a warm-up
> request. The expensive part of this is initializing your
> PersistenceManagerFactory/EntityManagerFactory, not establishing a datastore
> connection.
>
> On Tue, Jun 1, 2010 at 8:12 PM, Rahul Juneja <[email protected]>wrote:
>
>> Ikai,
>> The problem is that i am not sure when the values in the cache will be
>> accessed. but anyways i have implemented it in such a way that if the value
>> is not found in cache it goes to database to fetch it, but another issue
>> there is that if you are making the database connection first time after the
>> new jvm instance has been kicked off as it happens in Appengine,  db
>> connection takes a while, sometimes around 6-7 seconds, which is kind of
>> slow.
>>
>> Nicolas,
>> Thats the reason i am fetching the data if not found in cache.
>>
>>
>> Thanks,
>> Rahul
>>
>> ----------------------------------------------------------
>> Rahul Juneja
>> http://techlabs.thoughtclicks.com
>>
>>
>> On Tue, Jun 1, 2010 at 9:41 PM, Ikai L (Google) <[email protected]>wrote:
>>
>>> The items will get flushed if they are not getting used. If you're using
>>> items once every 24 hours ... you probably do not need a cache. Use the
>>> datastore instead. Rather than prevent the items from being flushed, build
>>> the ability to regenerate the cache into your system or don't even bother
>>> with Memcache.
>>>
>>> On Tue, Jun 1, 2010 at 6:24 PM, Rahul Juneja <[email protected]>wrote:
>>>
>>>> Ikai,
>>>>
>>>> I think you are right that the cache values are expiring via LRU as
>>>> sometimes only some elements of the cache are flushed.
>>>> But the question is my cache only has 20-30 entries and out of that 10
>>>> least recently used entries are being flushed. Is there any way i can
>>>> prevent this flushing as i don't want to flush if the cache is so small
>>>> instead i want the cache only to flush LRU elements when the cache grows in
>>>> size to maybe 100,000 entries.
>>>>
>>>> Any clues ?
>>>>
>>>> Thanks,
>>>> Rahul
>>>>
>>>> ----------------------------------------------------------
>>>> Rahul Juneja
>>>> http://techlabs.thoughtclicks.com
>>>>
>>>>
>>>> On Tue, Jun 1, 2010 at 6:56 PM, Ikai L (Google) <[email protected]>wrote:
>>>>
>>>>> No, there isn't a default expiration. How are you setting values to the
>>>>> cache? Could you be expiring the items via LRU? That is - you're not using
>>>>> the items in the cache, instead setting other items and pushing the older,
>>>>> unused items out?
>>>>>
>>>>> On Wed, May 26, 2010 at 6:43 PM, Rahul <[email protected]> wrote:
>>>>>
>>>>>> I have a  memcache and not to mention it does live between different
>>>>>> jvm instances when new jvm instances starts, i can access the cache
>>>>>> but once a while i don't find any values in cache and this happened
>>>>>> twice in last 24 hours. Is there any default expiration which is less
>>>>>> then 24-48 hours which i am not aware of.
>>>>>>
>>>>>> Any help or pointers on this is appreciated.
>>>>>>
>>>>>> Thanks,
>>>>>> Rahul
>>>>>>
>>>>>> --
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>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Ikai Lan
>>>>> Developer Programs Engineer, Google App Engine
>>>>> Blog: http://googleappengine.blogspot.com
>>>>> Twitter: http://twitter.com/app_engine
>>>>> Reddit: http://www.reddit.com/r/appengine
>>>>>
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>>>
>>>
>>>
>>> --
>>> Ikai Lan
>>> Developer Programs Engineer, Google App Engine
>>> Blog: http://googleappengine.blogspot.com
>>> Twitter: http://twitter.com/app_engine
>>> Reddit: http://www.reddit.com/r/appengine
>>>
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>
>
>
> --
> Ikai Lan
> Developer Programs Engineer, Google App Engine
> Blog: http://googleappengine.blogspot.com
> Twitter: http://twitter.com/app_engine
> Reddit: http://www.reddit.com/r/appengine
>
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