Design Project 2: Errata and Amendments Log

Last updated: $Date: 2005/05/01 22:55:37 $

May 1, 2005, Section 3.4: In the following paragraph, added "In your description of done(), be sure to clearly indicate the commit point as well as how the APU ensures that a partially completed call to done() is completely undone or redone."

May 1, 2005, Section 3.4: Changed APU modification atomicity requirement (3) from "once done has been called the pages will be written to the archive, even if the web server fails, assuming that it recovers eventually" to "If the APU crashes during the call to done, the pages may or may not be visible, depending on whether the implementation of done() has reached its commit point or not."

April 25, 2005, Section 2.5: Amended to state: "You are only required to provide data integrity when at most one archive server has been compromised. You may assume the the FWS is never compromised."

April 18, 2005, Section 2.1: There was another error in the math; we said 10 KB was 10^5 bytes, when it is actually 10^4 bytes. To make the math consistent, we have changed the average size of a page from 10 KB to 100 KB. As before, on average, each node still stores 10 GB of data.

April 11, 2005, Section 2.1: We changed the number of servers from 10,000 to 100,000 so that the calculation at the end of this section is correct. As was intended in the previous version, on average, each node stores 10 GB of data.

April 8, 2005, Section 3.4: changed "...if it calls open twice without a close in between..." to "...if it calls start twice without a done in between..." Made name of mapAMs consistent.

Bibliography: fixed reference.

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