Hi Hongxu! It might be best to go through JIRA comments. Some of them have design docs too. e.g. https://issues.apache.org/jira/browse/HDFS-265 , https://issues.apache.org/jira/browse/HDFS-744 etc.
I know there may be some windy conversations, but the good thing about open-source is that all these deliberations are for everyone to see. HTH Ravi. On Mon, Jul 31, 2017 at 3:13 AM, Hongxu Ma <inte...@outlook.com> wrote: > Hi Dev > In short, is there a full introduction to hdfs consistency model? > > I have already read some miscellaneous stuffs, e.g. > - some simple scenario > - read+read, ok > - write+write, forbidden (guaranteed be lease) > - design doc of append, truncate > - hflush/hsync > - top pages of google "hdfs consistency model" > > But I didn't find a detailed doc/link to clarify this topic, especially > how to deal with concurrent read+write, e.g.: > Can a later reader can read the contents which the writer (doesn't close > the file yet) appended? Is hflush/hsync the only ways to ensure the > consistency? etc.. > > I known the GFS paper has a specific section to clarify this topic, so I > think hdfs may has a similar one. > Very thanks for helpful link. > > > -- > Regards, > Hongxu. >
