[ https://issues.apache.org/jira/browse/HDDS-1512?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Bharat Viswanadham updated HDDS-1512: ------------------------------------- Status: Patch Available (was: Open) > Implement DoubleBuffer in OzoneManager > -------------------------------------- > > Key: HDDS-1512 > URL: https://issues.apache.org/jira/browse/HDDS-1512 > Project: Hadoop Distributed Data Store > Issue Type: Sub-task > Reporter: Bharat Viswanadham > Assignee: Bharat Viswanadham > Priority: Major > Labels: pull-request-available > Time Spent: 20m > Remaining Estimate: 0h > > This Jira is created to implement DoubleBuffer in OzoneManager to flush > transactions to OM DB. > > h2. Flushing Transactions to RocksDB: > We propose using an implementation similar to the HDFS EditsDoubleBuffer. We > shall flush RocksDB transactions in batches, instead of current way of using > rocksdb.put() after every operation. At a given time only one batch will be > outstanding for flush while newer transactions are accumulated in memory to > be flushed later. > > In DoubleBuffer it will have 2 buffers one is currentBuffer, and the other is > readyBuffer. We add entry to current buffer, and we check if another flush > call is outstanding. If not, we flush to disk Otherwise we add entries to > otherBuffer while sync is happening. > > In this if sync is happening, we shall add new requests to other buffer and > when we can sync we use *RocksDB batch commit to sync to disk, instead of > rocksdb put.* > > Note: If flush to disk is failed on any OM, we shall terminate the > OzoneManager, so that OM DB’s will not diverge. Flush failure should be > considered as catastrophic failure. > > Scope of this Jira is to add DoubleBuffer implementation, integrating to > current OM will be done in further jira's. > -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org