[LUCENE-9879] errorprone cause large slowdown of compileJava/compileTestJava

• Type: Task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 9.0
• Lucene Fields: New
• Assignee: Dawid Weiss
• Reporter: Robert Muir
• Created: 26/Mar/21 03:18
• Updated: 28/Aug/22 16:19
• Resolved: 28/Mar/21 11:16

Description

Errorprone hooks itself into the java compiler (compileJava/compileTestJava). So this static analysis runs, even if you are just recompiling to run tests.

It causes javac to run 3x slower at the moment.

With errorprone:

188.26 sec.  compileTestJava
180.24 sec.  compileJava

Without errorprone:

  52.54 sec.  compileTestJava
  49.26 sec.  compileJava

The worst part is: if you look at the config, essentially all error-prone checks are disabled. So we aren't getting value out of it, and it slows builds significantly.

I'd like to have a discussion about it:

• should we keep it enabled?
• should it really hook into compileJava/compileTests or maybe be a separate task (e.g. precommit only)

I'm raising this because it is so slow, that e.g. Uwe mentioned on other issues the possibility of switching to ECJ compiler to try to speed up builds, but, it turns out javac is actually fast. The slowness is error-prone.

For sure if we are going to use it, I'd like to at least turn on checks and get value out of the thing. But it is unclear to me how many of these checks aren't already met by javac or ecj (which frankly, we still haven't enabled to do good analysis yet, although the situation is improving)

cc uschindler dweiss

Issue Links

• is related to: LUCENE-9871 Achieve build system perfection (with progress)
• is related to: SOLR-16258 gradle should not normally use 'errorprone'
• links to: GitHub Pull Request #45