Today we continue discussing the best practice from storage engineering:

425) Another factor to improve data residency has been compression but this has required representations that are amenable to data processing internals..

426) There can be conflicts during replication cycle. For example, server A creates an object with a particular name at roughly the same time that Server B creates an object. with the same name. The conflict reconciliation process kicks in at the next replication cycle. The server looks for the version numbers of the updates and whichever is higher wins the conflict. If the version numbers are same, whichever attribute was changed at a later time wins the conflict.

427) If an object is moved to a parent that is now deleted, that object is placed in the lost and found container.

428) The single-master replication has following drawbacks: it has a single point of failure, there's geographic distance from master to clients performing the updates, and less efficient replication due to single originating location of updates. With multi-master replication, these can be avoided but they must be made part of a topology and the way the masters replicate with each other must be defined.

429) Some replication techniques use background loading where the data is loaded offline before being made available online. This is especially useful when the process of loading can take a long time.

430) Availability of a service is improved by adding a cluster instead of a server. On the other hand, processes involved in background loading can use a primary server together with secondary servers. In such cases, a primary server is authoritative but a secondary server can serve the content when primary is unavailable.

#codingexercise
In a game of collecting coins of different value from a sequence, is it better to go first or second ?

int getPlayer(List<int> sequence) { 

       Int player1Collection = GetCoins(sequence, 0, sequence.size() - 1);  

       Int player2Collection = Math.max(GetCoins(sequence, 1, sequence.size() - 1), GetCoins(sequence, 0, sequence.size() - 2)); 

      List<int> collections = Arrays.asList(player1Collection, player2Collection); 

      Int max = Collections.max(collections); 

      Return collections.indexOf(max); 

}