You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@ozone.apache.org by "Ritesh H Shukla (Jira)" <ji...@apache.org> on 2021/07/20 04:02:00 UTC
[jira] [Updated] (HDDS-2324) Enhance locking mechanism in
OzoneManger
[ https://issues.apache.org/jira/browse/HDDS-2324?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Ritesh H Shukla updated HDDS-2324:
----------------------------------
Summary: Enhance locking mechanism in OzoneManger (was: Enhance locking mechanism in OzoneMangaer)
> Enhance locking mechanism in OzoneManger
> ----------------------------------------
>
> Key: HDDS-2324
> URL: https://issues.apache.org/jira/browse/HDDS-2324
> Project: Apache Ozone
> Issue Type: Bug
> Components: Ozone Manager
> Reporter: Rajesh Balamohan
> Assignee: Rakesh Radhakrishnan
> Priority: Critical
> Labels: Triaged, performance
> Attachments: om_lock_100_percent_read_benchmark.svg, om_lock_reader_and_writer_workload.svg
>
>
> OM has reentrant RW lock. With 100% read or 100% write benchmarks, it works out reasonably fine. There is already a ticket to optimize the write codepath (as it incurs reading from DB for key checks).
> However, when small amount of write workload (e.g 3-5 threads) is added to the running read benchmark, throughput suffers significantly. This is due to the fact that the reader threads would get blocked often. I have observed around 10x slower throughput (i.e 100% read benchmark was running at 12,000 TPS and with couple of writer threads added to it, it goes down to 1200-1800 TPS).
> 1. Instead of single write lock, one option could be good to scale out the write lock depending on the number of cores available in the system and acquire relevant lock by hashing the key.
> 2. Another option is to explore if we can make use of StampedLocks of JDK 8.x, which scales well when multiple readers and writers are there. But it is not a reentrant lock. So need to explore whether it can be an option or not.
>
>
>
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@ozone.apache.org
For additional commands, e-mail: issues-help@ozone.apache.org