Extremely slow in autocompletion & code analysis for Kotlin projects in Intellij IDEA

Question

We have a project on IDEA that consists of a couple med sized Java packages and one very small Kotlin package (5 files). I noticed performance is fine with any Java packages, bu

Answer 1

The problem visible in your snapshot is resolved in Kotlin 1.1.4. As of this writing, it's available as an EAP (Early Access Preview) release; the final version will be released soon (and bundled with IntelliJ IDEA 2017.2.2).

Answer 2

I recently ran into this with a Kotlin gradle multi module project. I managed to get back to a good code analysis and completion speed by massively increasing my memory settings in the vmoptions, this is what they look like now

-Xms512m
-Xmx16384m
-XX:ReservedCodeCacheSize=960m
-XX:+UseConcMarkSweepGC
-XX:SoftRefLRUPolicyMSPerMB=100
-ea
-XX:CICompilerCount=2
-Dsun.io.useCanonPrefixCache=false
-Djava.net.preferIPv4Stack=true
-Djdk.http.auth.tunneling.disabledSchemes=""
-XX:+HeapDumpOnOutOfMemoryError
-XX:-OmitStackTraceInFastThrow
-Djdk.attach.allowAttachSelf=true
-Dkotlinx.coroutines.debug=off
-Djdk.module.illegalAccess.silent=true
-Dawt.useSystemAAFontSettings=lcd
-Dsun.java2d.renderer=sun.java2d.marlin.MarlinRenderingEngine
-Dsun.tools.attach.tmp.only=true

Answer 3

I've reached out to JetBrian and submitted a request to YouTrack. After reviewing the CPU snapshot, looks like upgrading the Kotlin plugin 1.1.4-eap which includes a major fix in performance will fix the issue. Just tried it and it worked!

Answer 4

Still happens in Kotlin 1.3.50. Got resolved by disabling Add unambiguous imports on the fly in Settings > Editor > General > Auto Import