At the Google Io Conference, Google App Engine (hereinafter referred to as the GAE) team announced the release of GAE 1.5.0. This version contains a lot of changes, which will increase the control on which application can run on the infrastructure.
One of the key changes is to run an instance for a long time. Previously, single thread requests are automatically launched and terminated according to the application’s load; and the throughput is added to the data to be processed, which is not suitable for all applications. The new Backends allows for a long time to run instant sets of memory and CPU requirements. They can be a constant resident (for the start and stop of the instance) or dynamic (they are typically terminated when they are required). Although threads are generally not allowed, these background instances can be maintained in the memory cache, and can serve multiple requests at a time through the Max-ConcURrent-Requests parameter.
In addition, the PULL queue can be used to allow instance request tasks instead of pushing tasks to a single instance. This will be a code and architectural level for those who wish to enjoy the advantages of different calculation models. New Taobao women’s brand
The last key change is to use high replication datastore as the default option, which reduces the cost related to options.
In the next year
In addition, it looks quite interesting in the next year, GAE will be separated from the preview of the preview this year, becoming the official product of Google, although there is no exact date.
One of the changes is to consolidate the GAE Business Edition, which was originally announced in Google Io 2010 for all GAE users. This will result in changes in price structure, in addition to the service level agreement and service terms of the new normal runtime. Free application is still available, but there are more stringent limits – however, in addition to the cost of use, payment applications require $ 9 per month. There is also a primary account option, which provides a unified fees for each application (but still charges).
The cost also needs to be re-adjusted, from the CPU utilization rate to a CPU instance hour. More details You can view the App Engine price page. High replication storage and master / slave data storage are $ 0.24 per g.
Go forward, advance …
Although GAE is originally supported by Python applications, it quickly became a multi-language that supports Java applications. With the release of 1.5.0, the SDK supports Go a development language for App Engine, and will soon be used in 1.5.0 deployment. You can download the Linux and OSX 32/64-bit architectural SDK.
The Go language on GAE is a subset of the entire Go language, no Unsafe and Syscall libraries, but includes Appengine-specific APIs, such as Datastore, Blobstore, and more.
Finally, like other languages, SDK said that only a single CPU thread is supported when the Go language is run. So, although Goroutines (parallel program in Go language is called Goroutines) and channels, there is only one single thread. The announcement pointed out that this restriction may be canceled in the future.
Look at the demo, as well as the source code, as well as documentation on the GO supported in App Engine.