December 2023
Intermediate to advanced
464 pages
12h 35m
English
Content preview from Patterns of Distributed Systems
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
Start your free trial
Chapter 20
Key-Range Partitions
Partition data in sorted key ranges to efficiently handle range queries.
Problem
To split data across a set of cluster nodes, each data item needs to be mapped to a node. If users want to query a range of keys, specifying only the start and end key, all partitions will need to be queried for the values to be acquired. Querying every partition for a single request is far from optimal.
Take a key-value store as an example. We can store the author names using hash-based mapping, as in Fixed Partitions (Table 20.1).
Table 20.1 Key Mapping to Cluster Nodes Using Hash of a Key
Keys |
Hash |
Partition = Hash % Number of partitions (9) |
Node |
|---|---|---|---|
alice |
133299819613694460644197938031451912208 |
0 |
0 |
bob |
63479738429015246738359000453022047291 ... |