Hi Gwyn,
It basically adds a small delay before a transaction applies, but
with facilities to grab consistent snapshots of entity groups when
needed. If you're not seeing any difference, then you're app is
probably doing ancestor queries or gets by key -- which is good.
You can check out the code:
http://code.google.com/p/googleappengine/source/browse/trunk/python/google/appengine/datastore/datastore_stub_util.py#1310
Here is some code to demonstrate what the option does:
import uuid
import logging
class T(db.Model):
index = db.StringProperty()
for _ in xrange(100):
index = str(uuid.uuid4())
T(key_name=index, index=index).put()
# put a time.sleep(xx) here to see how it works.
# This will usually not work on prod HR datastore.
t = T.all().filter('index', index).get()
if not t:
logging.info('NoTing for you.')
# This should always work.
t_by_key = T.get_by_key_name(index)
if not t_by_key:
logging.error('You should never see this')
Robert
On Wed, Jun 22, 2011 at 07:01, Gwyn Howell <gwyn.how...@appogee.co.uk> wrote:
> In version Version 1.5.1 just released, one of the updates was:
> The development server's datastore implementation now contains logic that
> closely replicates the consistency guarantees of the High Replication
> datastore. To use, run the dev_appserver with the
> flag --high_replication set to True.
>
> What does this actually do? There must be an advantage of turning it on, but
> I can't see any difference. Is it just a different way to store the data in
> the local datastore?
>
> --
> You received this message because you are subscribed to the Google Groups
> "Google App Engine" group.
> To view this discussion on the web visit
> https://groups.google.com/d/msg/google-appengine/-/AAOJsS2h-FIJ.
> To post to this group, send email to google-appengine@googlegroups.com.
> To unsubscribe from this group, send email to
> google-appengine+unsubscr...@googlegroups.com.
> For more options, visit this group at
> http://groups.google.com/group/google-appengine?hl=en.
>
--
You received this message because you are subscribed to the Google Groups
"Google App Engine" group.
To post to this group, send email to google-appengine@googlegroups.com.
To unsubscribe from this group, send email to
google-appengine+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/google-appengine?hl=en.
