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Thomas Nikolay edited comment on MNG-6311 at 5/23/18 10:07 AM: --------------------------------------------------------------- Our Company runs in the same problem with very large POM structures and imports. This is currently a blocker to migrate from 3.3.9 to 3.5.X. The same POM with JDK 1.8.0_112 * with MVN 3.3.9 duration = 6 seconds * with MVN 3.5.2 duration = 107 seconds I analysed with Yourkit [^Call-tree-–-All-threads-together.html] was (Author: tnikolay): Our Company runs in the same problem with very large POM structures and imports. This is currently a blocker to migrate from 3.3.9 to 3.5.X. I analysed with Yourkit [^Call-tree-–-All-threads-together.html] > Maven intolerably slow when import scope used heavily in large project > ---------------------------------------------------------------------- > > Key: MNG-6311 > URL: https://issues.apache.org/jira/browse/MNG-6311 > Project: Maven > Issue Type: Bug > Components: core, Performance > Affects Versions: 3.5.0, 3.5.2 > Reporter: David Churcher > Priority: Major > Labels: performance > Attachments: Call-tree-–-All-threads-together.html, > anon-hierarchy-maven-output.zip, modelcachefix.diff > > > I have a build performance problem that is identical to MNG-5312, and has > appeared since MNG-6030 in Maven v3.5.0 reversed the patch for MNG-5312, > removing the ModelCache from some of the overloads for > DefaultProjectBuilder.build. > As in MNG-5312 the problem is in a large proprietary project. It uses up to 8 > levels of parent POMs, many of which use the import scope and have large > dependency-management sections, and has hundreds of dependencies that also > use the same parent POM hierarchy. Adding some logging shows that Maven does > over 800,000 uncached reads of parent POM files, which takes about half an > hour. With model caching this goes down to a few seconds. > I've attached a patch that fixes this by using a class-level ModelCache in > DefaultProjectBuilder. This does not suffer from the memory usage problems > reported in MNG-6030. -- This message was sent by Atlassian JIRA (v7.6.3#76005)