Warning: pg_query(): Query failed: ERROR: missing chunk number 0 for toast value 29512337 in pg_toast_2619 in /dati/webiit-old/includes/database.pgsql.inc on line 138 Warning: ERROR: missing chunk number 0 for toast value 29512337 in pg_toast_2619 query: SELECT data, created, headers, expire, serialized FROM cache_page WHERE cid = 'https://www-old.iit.cnr.it/en/node/49434' in /dati/webiit-old/includes/database.pgsql.inc on line 159 Warning: pg_query(): Query failed: ERROR: missing chunk number 0 for toast value 29512337 in pg_toast_2619 in /dati/webiit-old/includes/database.pgsql.inc on line 138 Warning: ERROR: missing chunk number 0 for toast value 29512337 in pg_toast_2619 query: SELECT data, created, headers, expire, serialized FROM cache_page WHERE cid = 'https://www-old.iit.cnr.it/en/node/49434' in /dati/webiit-old/includes/database.pgsql.inc on line 159 Roaring Bitmaps: Implementation of an Optimized Software Library | IIT - CNR - Istituto di Informatica e Telematica
IIT Home Page CNR Home Page

Roaring Bitmaps: Implementation of an Optimized Software Library

Compressed bitmap indexes are used in systems such as Git or Oracle to accelerate queries. They represent sets and often support operations such as unions, intersections, differences, and symmetric differences. Several important systems such as Elasticsearch, Apache Spark, Netflix’s Atlas, LinkedIn’s Pivot, Metamarkets’ Druid, Pilosa, Apache Hive, Apache Tez, Microsoft Visual Studio Team Services and Apache Kylin rely on a specific type of compressed bitmap index called Roaring. We present an optimized software library written in C implementing Roaring bitmaps: CRoaring. It benefits from several algorithms designed for the single-instruction-multiple-data (SIMD) instructions available on commodity processors. In particular, we present vectorized algorithms to compute the intersection, union, difference and symmetric difference between arrays. We benchmark the library against a wide range of competitive alternatives, identifying weaknesses and strengths in our software. Our work is available under a liberal open-source license. 

 


Software: Practice and Experience, 2017

External authors: Daniel Lemire (Universite ́ du Que ́bec), Owen Kaser (UNB Saint John), Nathan Kurz (Orinda), Chris O’Hara (Kissmetrics), Francois Saint-Jacques (AdGear Technologies), Gregory Ssi-Yan-Kai ()
IIT authors:

Type: Contributo in rivista non ISI
Field of reference: Information Technology and Communication Systems

File: roaring.pdf

Activity: Analisi della qualità del Sistema DNS del ccTLD .it