Here's our January 2021 roundup of links from across the web that could be relevant to you:
1. Storing Cold Metadata with Alki (Dropbox)
Dropbox shared insights into Alki, the petabyte-scale metadata store it designed for infrequently accessed metadata (“cold data”). The post details how one-size-fits-all database Edgestore was reaching capacity limits, and why audit logs were a good candidate to be moved elsewhere than on costly SSDs. After considering off-the-shelf options, the team settled on building its own solution on top of AWS services: Alki; with DynamoDB as the hot store, and S3 as the cold store. Like HBase or Cassandra, Alki is based on log-structured merge-trees (LSM trees), but is better suited to handle hot-then-cold audit logs, as well as future use cases at Dropbox.