[
https://issues.apache.org/jira/browse/HDDS-14719?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Wei-Chiu Chuang updated HDDS-14719:
-----------------------------------
Epic Link: HDDS-13747
> Open HA checkpoint RocksDB as read-only to prevent unnecessary compaction
> during txn-info verification
> ------------------------------------------------------------------------------------------------------
>
> Key: HDDS-14719
> URL: https://issues.apache.org/jira/browse/HDDS-14719
> Project: Apache Ozone
> Issue Type: Bug
> Components: OM HA, SCM HA, Snapshot
> Reporter: Saketa Chalamchala
> Assignee: Saketa Chalamchala
> Priority: Major
> Labels: pull-request-available
> Fix For: 2.2.0
>
>
> Discovered when testing install checkpoint from leader OM.
> When the downloaded checkpoint from the leader is opened to verify if the
> checkpoint's txn info > OM db's txn info on the target OM,
> RocksDB can run auto-compaction inside the checkpoint (om.db.candidate/om.db)
> directory and then delete SSTs, causing the follower’s installed DB file set
> to differ from the leader checkpoint and in OM's case the untracked
> compaction can cause snapdiff to perform poorly because efficient diff is not
> possible if the compaction history is not preserved.
> In general, it would be best to open rocksDB in temporary checkpoint
> locations in read-only mode to perform read only operations (like txn info
> validation)
> om.db after replacing with installed checkpoint
> {code:java}
> [/var/lib/hadoop-ozone/om/data520340/om.db]# ls -al
> ...
> -rw-r--r-- 1 hdfs hdfs 177162 Feb 24 15:24 LOG
> -rw-r--r-- 1 hdfs hdfs 122650 Feb 24 15:17 LOG.old.1771975134401496
> -rw-r--r-- 1 hdfs hdfs 195175 Feb 24 15:23 LOG.old.1771975455672651
> [/var/lib/hadoop-ozone/om/data520340/om.db]# vim LOG.old.1771975134401496
> ...
> 2026/02/24-15:17:45.977142 140620264883968
> [/compaction/compaction_job.cc:1950] [deletedTable] [JOB 2] Compacting 4@0 +
> 1@6 files to L6, score 1.00
> 2026/02/24-15:17:45.977152 140620264883968
> [/compaction/compaction_job.cc:1954] [deletedTable] Compaction start summary:
> Base version 26 Base level 0, inputs: [166(1110B) 158(3197B) 151(7595B)
> 144(3777B)], [130(11KB)]
> ...
> 2026/02/24-15:17:45.989272 140620264883968 [le/delete_scheduler.cc:77]
> Deleted file
> /var/lib/hadoop-ozone/om/ozone-metadata520340/snapshot/om.db.candidate/om.db/000166.sst
> immediately, rate_bytes_per_sec 0, total_trash_size 0 max_trash_db_ratio
> 0.250000
> 2026/02/24-15:17:45.989295 140620264883968 [le/delete_scheduler.cc:77]
> Deleted file
> /var/lib/hadoop-ozone/om/ozone-metadata520340/snapshot/om.db.candidate/om.db/000158.sst
> immediately, rate_bytes_per_sec 0, total_trash_size 0 max_trash_db_ratio
> 0.250000
> ...
> {code}
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
