What platform? Java or Python?

On Mon, Nov 22, 2010 at 11:03 AM, Alfred Fuller <
[email protected] <arfuller%[email protected]>> wrote:

> This sound like what would happen if read_policy=EVENTUAL_CONSISTENCY is
> enabled. Are you setting this anywhere?
>
>
> On Fri, Nov 19, 2010 at 9:37 AM, Sanjay <[email protected]> wrote:
>
>> I'm pretty sure the data consistency is not in our application because
>> of the characteristics of the problem.  I do not use Memcache or a per-
>> instance in-memory cache, and perform direct reads from the datastore
>> as the application is high-write, low-read.
>>
>> I can reproduce this problem at will by just refreshing a page that
>> reloads the data from the datastore.  About 20% of the time I get an
>> incorrect value.  The data is being written using a cron that fires
>> every 10 minutes, and there are no other writers to this entry.  Thus
>> I'm pretty sure that it's not being performed by an incorrect write.
>> From the characteristics, it seems to me like there's an instance
>> serving the application that is stale and serving bad data.  Perhaps
>> this instance is in a different datacenter than the main set of
>> instances, and thus Megastore replication has fallen behind, or is in
>> an inconsistent state?
>>
>> I've been working with AppEngine for nearly the last year, and haven't
>> seen this bizarre behavior before.
>>
>> Is there a way to escalate such issues for someone in Google to have a
>> look?
>>
>> Thanks!
>>
>> On Nov 19, 8:31 am, Robert Kluin <[email protected]> wrote:
>> > I did not see anything quite like that.  It sort of sounds like you
>> > might have a cache bug.  Perhaps instance variables are being used as
>> > cache?
>> >
>> > Robert
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>> > On Fri, Nov 19, 2010 at 04:04, Sanjay <[email protected]> wrote:
>> > > Hello,
>> >
>> > > Starting earlier today around the time of the App Engine deploy
>> > > outage, I'm seeing a lot of data inconsistency.  Data written several
>> > > minutes earlier cannot be read back consistently.  Even more
>> > > surprisingly, just retrying the operation multiple times yields older
>> > > versions of the same data.  Is anyone else seeing this?
>> >
>> > > Thanks,
>> > > Sanjay
>> >
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