Re: [appengine-java] Re: Eventually consistent reads and JDO
I finally figured it out, its on the Datastore config level. DatastoreServiceConfig config = DatastoreServiceConfig.Builder.withReadPolicy(new ReadPolicy(Consistency. EVENTUAL)); DatastoreService dss = DatastoreServiceFactory.getDatastoreService(config); I thought it would have been on the Query object as it is in the JDO example posted in the blog. I was using a singleton as I thought we were only meant to instantiate one DatastoreService instance and reuse it?? On Fri, Apr 2, 2010 at 1:04 AM, lepah mfarn...@gmail.com wrote: Hi there, How can I use this with the low level datastore, I've looked around in the JavaDocs and found ReadPolicy.Consistency but couldn't find anywhere to set it. It could be just me as it's 1AM. Would love to try it out. On Apr 1, 11:39 am, Isdal tomas.is...@gmail.com wrote: Thanks Ikai! I noticed that the docs are updated now too. This page has a couple examples on it as well: http://code.google.com/appengine/docs/java/datastore/usingjdo.html // Tomas On Mar 30, 3:57 pm, Ikai L (Google) ika...@google.com wrote: Yep. The example is documented here: http://googleappengine.blogspot.com/2010/03/read-consistency-deadline. .. http://googleappengine.blogspot.com/2010/03/read-consistency-deadline.. .Query q = pm.newQuery(Employee.class); q.addExtension(datanucleus.appengine.datastoreReadConsistency, EVENTUAL); On Fri, Mar 26, 2010 at 5:12 PM, Isdal tomas.is...@gmail.com wrote: Hi all, Thanks for all new new features in 1.3.2! I was just wondering if it is possible to use the ReadPolicy.Consistency.EVENTUAL feature and still use the JDO interface. I am currently getting a PersistenceManager with: JDOHelper.getPersistenceManagerFactory(transactions- optional); Is there a way to tell the PersistenceManager to tell the datastore to accept eventually consistent reads? Most of my app can handle stale data, and any performance improvement would be great! Thanks! // Tomas -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.comgoogle-appengine-java%2B unsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Enginehttp:// googleappengine.blogspot.com|http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Eventually consistent reads and JDO
You're probably best off creating new instances of DatastoreService. There are some good points raised here: https://groups.google.com/group/google-appengine-java/browse_thread/thread/e19b792042b2ff9b# On Fri, Apr 2, 2010 at 1:26 AM, Matt Farnell mfarn...@gmail.com wrote: I finally figured it out, its on the Datastore config level. DatastoreServiceConfig config = DatastoreServiceConfig.Builder.withReadPolicy(new ReadPolicy(Consistency. EVENTUAL)); DatastoreService dss = DatastoreServiceFactory.getDatastoreService(config); I thought it would have been on the Query object as it is in the JDO example posted in the blog. I was using a singleton as I thought we were only meant to instantiate one DatastoreService instance and reuse it?? On Fri, Apr 2, 2010 at 1:04 AM, lepah mfarn...@gmail.com wrote: Hi there, How can I use this with the low level datastore, I've looked around in the JavaDocs and found ReadPolicy.Consistency but couldn't find anywhere to set it. It could be just me as it's 1AM. Would love to try it out. On Apr 1, 11:39 am, Isdal tomas.is...@gmail.com wrote: Thanks Ikai! I noticed that the docs are updated now too. This page has a couple examples on it as well: http://code.google.com/appengine/docs/java/datastore/usingjdo.html // Tomas On Mar 30, 3:57 pm, Ikai L (Google) ika...@google.com wrote: Yep. The example is documented here: http://googleappengine.blogspot.com/2010/03/read-consistency-deadline. .. http://googleappengine.blogspot.com/2010/03/read-consistency-deadline.. .Query q = pm.newQuery(Employee.class); q.addExtension(datanucleus.appengine.datastoreReadConsistency, EVENTUAL); On Fri, Mar 26, 2010 at 5:12 PM, Isdal tomas.is...@gmail.com wrote: Hi all, Thanks for all new new features in 1.3.2! I was just wondering if it is possible to use the ReadPolicy.Consistency.EVENTUAL feature and still use the JDO interface. I am currently getting a PersistenceManager with: JDOHelper.getPersistenceManagerFactory(transactions- optional); Is there a way to tell the PersistenceManager to tell the datastore to accept eventually consistent reads? Most of my app can handle stale data, and any performance improvement would be great! Thanks! // Tomas -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.comgoogle-appengine-java%2B unsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Enginehttp:// googleappengine.blogspot.com|http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
Re: [appengine-java] Re: Eventually consistent reads and JDO
Since it is not explicitly documented as thread safe, you should not make this assumption. Basically, it's the same as us telling you not to use undocumented methods because they *can* and *have* changed. On Fri, Apr 2, 2010 at 11:46 AM, Matt Farnell mfarn...@gmail.com wrote: Hi Ikai, It says in that forum that it's 'probably' not thread safe, so is it thread safe or not? If its not threadsafe then we should never use a singleton instance. Can you give us a more definitive answer such as it's not threadsafe so never cache the instance, or it is threadsafe so therefore it is up to us. It would be very helpful. thanks, Matt On Fri, Apr 2, 2010 at 9:54 AM, Ikai L (Google) ika...@google.com wrote: You're probably best off creating new instances of DatastoreService. There are some good points raised here: https://groups.google.com/group/google-appengine-java/browse_thread/thread/e19b792042b2ff9b# On Fri, Apr 2, 2010 at 1:26 AM, Matt Farnell mfarn...@gmail.com wrote: I finally figured it out, its on the Datastore config level. DatastoreServiceConfig config = DatastoreServiceConfig.Builder.withReadPolicy(newReadPolicy(Consistency. EVENTUAL)); DatastoreService dss = DatastoreServiceFactory.getDatastoreService(config); I thought it would have been on the Query object as it is in the JDO example posted in the blog. I was using a singleton as I thought we were only meant to instantiate one DatastoreService instance and reuse it?? On Fri, Apr 2, 2010 at 1:04 AM, lepah mfarn...@gmail.com wrote: Hi there, How can I use this with the low level datastore, I've looked around in the JavaDocs and found ReadPolicy.Consistency but couldn't find anywhere to set it. It could be just me as it's 1AM. Would love to try it out. On Apr 1, 11:39 am, Isdal tomas.is...@gmail.com wrote: Thanks Ikai! I noticed that the docs are updated now too. This page has a couple examples on it as well: http://code.google.com/appengine/docs/java/datastore/usingjdo.html // Tomas On Mar 30, 3:57 pm, Ikai L (Google) ika...@google.com wrote: Yep. The example is documented here: http://googleappengine.blogspot.com/2010/03/read-consistency-deadline. .. http://googleappengine.blogspot.com/2010/03/read-consistency-deadline.. .Query q = pm.newQuery(Employee.class); q.addExtension(datanucleus.appengine.datastoreReadConsistency, EVENTUAL); On Fri, Mar 26, 2010 at 5:12 PM, Isdal tomas.is...@gmail.com wrote: Hi all, Thanks for all new new features in 1.3.2! I was just wondering if it is possible to use the ReadPolicy.Consistency.EVENTUAL feature and still use the JDO interface. I am currently getting a PersistenceManager with: JDOHelper.getPersistenceManagerFactory(transactions- optional); Is there a way to tell the PersistenceManager to tell the datastore to accept eventually consistent reads? Most of my app can handle stale data, and any performance improvement would be great! Thanks! // Tomas -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.comgoogle-appengine-java%2B unsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Enginehttp:// googleappengine.blogspot.com|http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.comgoogle-appengine-java%2bunsubscr...@googlegroups.com . For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en. -- Ikai Lan Developer Programs Engineer, Google App Engine http://googleappengine.blogspot.com | http://twitter.com/app_engine -- You received this message because you are subscribed to the Google Groups Google App Engine for Java group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send
