Editing P-Grid (section)

== Range queries in P-Grid ==

P-Grid partitions the key-space in a granularity adaptive to the load at that part of the key-space. Consequently, its possible to realize a P-Grid overlay network where each peer has similar storage load even for non-uniform load distributions. This network probably provides as efficient search of keys as traditional [[distributed hash table]]s (DHTs) do. Note that in contrast to P-Grid, DHTs work efficiently only for uniform load-distributions.<ref name="Pitoura">{{cite conference |last1=Pitoura|first1=Pitoura |last2=Ntarmos|first2=Nikos |last3=Triantafillou|first3=Peter |title=Replication, load balancing and efficient range query processing in DHTs |conference=International Conference on Extending Database Technology |date=2006 |pages=131–148|doi=10.1007/11687238_11}}</ref>

Hence we can use a lexicographic order preserving function to generate the keys, and still realize a load-balanced P-Grid network which supports efficient search of exact keys. Moreover, because of the preservation of lexicographic ordering, range queries can be done efficiently and precisely on P-Grid. The trie-structure of P-Grid allows different range query strategies, processed serially or in parallel, trading off message overheads and query resolution latency.<ref name="Datta">{{cite conference |title=Range queries in trie-structured overlays |conference=Fifth IEEE International Conference on Peer-to-Peer Computing |date=2005 |pages=57–66|doi=10.1109/P2P.2005.31|last1=Datta |first1=A. |last2=Hauswirth |first2=M. |last3=John |first3=R. |last4=Schmidt |first4=R. |last5=Aberer |first5=K. |isbn=0-7695-2376-5 |url=http://infoscience.epfl.ch/record/54360 }}</ref> Simple vector-based data storage architectural frameworks are also subject to variable query limitations within the P-Grid environment.<ref name="Oliker">{{cite journal |doi=10.1177/1094342006085020|title=Scientific Application Performance on Leading Scalar and Vector Supercomputering Platforms|journal=The International Journal of High Performance Computing Applications|volume=22|pages=5–20|year=2008|last1=Oliker|first1=Leonid|last2=Canning|first2=Andrew|last3=Carter|first3=Jonathan|last4=Shalf|first4=John|last5=Ethier|first5=Stéphane|s2cid=5347699}}</ref>