[ https://issues.apache.org/jira/browse/JENA-1615?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Andy Seaborne resolved JENA-1615. --------------------------------- Resolution: Fixed Assignee: Andy Seaborne Fix Version/s: Jena 3.10.0 > Compaction leaks file descriptors > --------------------------------- > > Key: JENA-1615 > URL: https://issues.apache.org/jira/browse/JENA-1615 > Project: Apache Jena > Issue Type: Bug > Components: Core, TDB2 > Affects Versions: Jena 3.8.0 > Environment: I reproduced the issue on the following environments: > * OS / Java: > ** MacOS 10.13.5 > Java 1.8.0_161 (Oracle) > ** Debian 9.5 > Java 1.8.0_181 (OpenJDK) > * Jena version 3.8.0 > * TDB2 mode: mapped > Reporter: Damien Obrist > Assignee: Andy Seaborne > Priority: Major > Fix For: Jena 3.10.0 > > Attachments: open_files_after_compaction_after_gc.png, > open_files_after_compaction_after_gc_with_fix.png, > open_files_after_compaction_before_gc.png, open_files_before_compaction.png > > > h3. Context > I'm using a TDB2 dataset in a long-running Scala application, in which the > dataset gets compacted regularly. After compactions, the application removes > the {{Data-xxxx}} folder of the previous generation. However, the > corresponding disk space isn't properly returned back to the OS, but is still > reported as being used by {{df}}. Indeed, {{lsof}} shows that the application > keeps open file descriptors that point to the old generation's files. Only > stopping / restarting the JVM frees the disk space for good. > h3. Reproduction steps > * Connect to an existing TDB2 dataset > {code} > val dataset = TDB2Factory.connectDataset("sample"){code} > * Check open files > [^open_files_before_compaction.png] > * Compact the dataset > {code}DatabaseMgr.compact(dataset.asDatasetGraph){code} > * Check open files (before garbage collection) > [^open_files_after_compaction_before_gc.png] > * Check open files (after garbage collection) > [^open_files_after_compaction_after_gc.png] > The last sceenshot shows that, even after garbage collection, there are still > open file descriptors pointing to the old generation {{Data-0001}}. > h3. Impact > Depending on how disk usage is being reported, this can be quite problematic. > In our case, we're running on an OpenShift infrastructure with limited > storage. After only a handful of compactions, the storage is considered full > and cannot be used anymore. -- This message was sent by Atlassian JIRA (v7.6.3#76005)