That's accurate. Performing a batch get to get a N entities from different entity groups is slower or HRD. As N increases the issue is more pronounced. This is because the datastore needs to fetch a consistent copy for each entity.
Placing these entities into a single entity group can help greatly. Fetching fewer entities initially, so that the UI updates quickly, and then fetching more as needed, is always a good idea. A great tool to help understand your use of the datastore is Appstats, which can be easily enabled and provides negligible overhead to most sites. (If you have a high traffic site, or don't want to enable Appstats in production for other reasons, you can easily deploy a non-default version of your app with Appstats enabled). Appstats will provide you a graphical overview of the datastore (and other RPC) calls you are making. On Thu, Aug 18, 2011 at 12:19 PM, Robert Kluin <robert.kl...@gmail.com>wrote: > When switching to the HR datastore, you might need to make some > adjustments. For instance, fetching a large list of keys from > multiple entity groups may be slower due to the transaction overhead. > So you might need to evaluate your use of entity groups. It may also > be that you've got a design that is making many datastore RPCs in > serial, that will probably be more of an issue when on HR since there > is a slightly higher average latency. > > > Robert > > > > > > On Thu, Aug 18, 2011 at 15:11, thstart <thst...@gmail.com> wrote: > > Let me share my experience. > > I was developing an AppEngine app for a year. > > It was very fast (extremely fast), with latency > 1 sec. > > When High Replication data-store was released I decided to give it > > a try and switched to it. Unfortunately the latency got >1 Sec > > sometimes > 2 Sec. The app worked a wile that way and because > > still in beta I could experiment. So I decided to go to Billed option > > to see if the reliability and more importantly the latency could improve. > > Unfortunately this do not affected latency. Then I decided to go back to > > Master/Slave - our customers mentioned immediately our app is 2 times > > faster - again < 1 Sec latency. Then I needed to add https which is > > very important for our app. This do not added significant latency so our > > customers are very happy with this solution. Soon we will go public. > > So the latency issue is a show stopper for high replication version > > and we would want to stay with master slave. > > Anybody with similar experience? > > Thank you, > > > > > > > > -- > > 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/-/P1c_gMSRtl0J. > > 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. > > -- Fred Sauer Developer Advocate Google Inc. 1600 Amphitheatre Parkway Mountain View, CA 94043 fre...@google.com -- 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.
