+1 nonbinding Thanks, Xiaoyu Hou
太上玄元道君 <dao...@apache.org> 于2024年2月6日周二 15:59写道： > > +1 nonbinding > > Matteo Merli <mme...@apache.org>于2024年2月6日 周二04:40写道： > > > https://github.com/apache/pulsar/pull/22009 > > > > ------------- > > > > # PIP-335: Support Oxia metadata store plugin > > > > # Motivation > > > > Oxia is a scalable metadata store and coordination system that can be used > > as the core infrastructure > > to build large scale distributed systems. > > > > Oxia was created with the primary goal of providing an alternative Pulsar > > to replace ZooKeeper as the > > long term preferred metadata store, overcoming all the current limitations > > in terms of metadata > > access throughput and data set size. > > > > # Goals > > > > Add a Pulsar MetadataStore plugin that uses Oxia client SDK. > > > > Users will be able to start a Pulsar cluster using just Oxia, without any > > ZooKeeper involved. > > > > ## Not in Scope > > > > It's not in the scope of this proposal to change any default behavior or > > configuration of Pulsar. > > > > # Detailed Design > > > > ## Design & Implementation Details > > > > Oxia semantics and client SDK were already designed with Pulsar and > > MetadataStore plugin API in mind, so > > there is not much integration work that needs to be done here. > > > > Just few notes: > > 1. Oxia client already provides support for transparent batching of read > > and write operations, > > so there will be no use of the batching logic in > > `AbstractBatchedMetadataStore` > > 2. Oxia does not treat keys as a walkable file-system like interface, with > > directories and files. Instead > > all the keys are independent. Though Oxia sorting of keys is aware of > > '/' and provides efficient key > > range scanning operations to identify the first level children of a > > given key > > 3. Oxia, unlike ZooKeeper, doesn't require the parent path of a key to > > exist. eg: we can create `/a/b/c` key > > without `/a/b` and `/a` existing. > > In the Pulsar integration for Oxia we're forcing to create all parent > > keys when they are not there. This > > is due to several places in BookKeeper access where it does not create > > the parent keys, though it will > > later make `getChildren()` operations on the parents. > > > > ## Other notes > > > > Unlike in the ZooKeeper implementation, the notification of events is > > guaranteed in Oxia, because the Oxia > > client SDK will use the transaction offset after server reconnections and > > session restarted events. This > > will ensure that brokers cache will always be properly invalidated. We will > > then be able to remove the > > current 5minutes automatic cache refresh which is in place to prevent the > > ZooKeeper missed watch issue. > > > > # Links > > > > Oxia: https://github.com/streamnative/oxia > > Oxia Java Client SDK: https://github.com/streamnative/oxia-java > > > > > > -- > > Matteo Merli > > <mme...@apache.org> > >
