https://kotlinlang.org logo
Channels
100daysofcode
100daysofkotlin
100daysofkotlin-2021
advent-of-code
aem
ai
alexa
algeria
algolialibraries
amsterdam
android
android-architecture
android-databinding
android-studio
androidgithubprojects
androidthings
androidx
androidx-xprocessing
anime
anko
announcements
apollo-kotlin
appintro
arabic
argentina
arkenv
arksemdevteam
armenia
arrow
arrow-contributors
arrow-meta
ass
atlanta
atm17
atrium
austin
australia
austria
awesome-kotlin
ballast
bangladesh
barcelona
bayarea
bazel
beepiz-libraries
belgium
benchmarks
berlin
big-data
books
boston
brazil
brikk
budapest
build
build-tools
bulgaria
bydgoszcz
cambodia
canada
carrat
carrat-dev
carrat-feed
chicago
chile
china
chucker
cincinnati-user-group
cli
clikt
cloudfoundry
cn
cobalt
code-coverage
codeforces
codemash-precompiler
codereview
codingame
codingconventions
coimbatore
collaborations
colombia
colorado
communities
competitive-programming
competitivecoding
compiler
compose
compose-android
compose-desktop
compose-hiring
compose-ios
compose-mp
compose-ui-showcase
compose-wear
compose-web
confetti
connect-audit-events
corda
cork
coroutines
couchbase
coursera
croatia
cryptography
cscenter-course-2016
cucumber-bdd
cyprus
czech
dagger
data2viz
databinding
datascience
dckotlin
debugging
decompose
decouple
denmark
deprecated
detekt
detekt-hint
dev-core
dfw
docs-revamped
dokka
domain-driven-design
doodle
dsl
dublin
dutch
eap
eclipse
ecuador
edinburgh
education
effective-kotlin
effectivekotlin
emacs
embedded-kotlin
estatik
event21-community-content
events
exposed
failgood
fb-internal-demo
feed
firebase
flow
fluid-libraries
forkhandles
forum
fosdem
fp-in-kotlin
framework-elide
freenode
french
fritz2
fuchsia
functional
funktionale
gamedev
ge-kotlin
general-advice
georgia
geospatial
german-lang
getting-started
github-workflows-kt
glance
godot-kotlin
google-io
gradle
graphic
graphkool
graphql
graphql-kotlin
graviton-browser
greece
grpc
gsoc
gui
hackathons
hacktoberfest
hamburg
hamkrest
helios
helsinki
hexagon
hibernate
hikari-cp
hire-me
hiring
hiring-french
hongkong
hoplite
http4k
hungary
hyderabad
image-processing
india
indonesia
inkremental
intellij
intellij-plugins
intellij-tricks
internships
introduce-yourself
io
ios
iran
israel
istanbulcoders
italian
jackson-kotlin
jadx
japanese
jasync-sql
java-to-kotlin-refactoring
javadevelopers
javafx
javalin
javascript
jdbi
jhipster-kotlin
jobsworldwide
jpa
jshdq
juul-libraries
jvm-ir-backend-feedback
jxadapter
k2-early-adopters
kaal
kafka
kakao
kalasim
kapt
karachi
karg
karlsruhe
kash_shell
kaskade
kbuild
kdbc
kgen-doc-tools
kgraphql
kinta
klaxon
klock
kloudformation
kmdc
kmm-español
kmongo
knbt
knote
koalaql
koans
kobalt
kobweb
kodein
kodex
kohesive
koin
koin-dev
komapper
kondor-json
kong
kontent
kontributors
korau
korean
korge
korim
korio
korlibs
korte
kotest
kotest-contributors
kotless
kotlick
kotlin-asia
kotlin-beam
kotlin-by-example
kotlin-csv
kotlin-data-storage
kotlin-foundation
kotlin-fuel
kotlin-in-action
kotlin-inject
kotlin-latam
kotlin-logging
kotlin-multiplatform-contest
kotlin-mumbai
kotlin-native
kotlin-pakistan
kotlin-plugin
kotlin-pune
kotlin-roadmap
kotlin-samples
kotlin-sap
kotlin-serbia
kotlin-spark
kotlin-szeged
kotlin-website
kotlinacademy
kotlinbot
kotlinconf
kotlindl
kotlinforbeginners
kotlingforbeginners
kotlinlondon
kotlinmad
kotlinprogrammers
kotlinsu
kotlintest
kotlintest-devs
kotlintlv
kotlinultimatechallenge
kotlinx-datetime
kotlinx-files
kotlinx-html
kotrix
kotson
kovenant
kprompt
kraph
krawler
kroto-plus
ksp
ktcc
ktfmt
ktlint
ktor
ktp
kubed
kug-leads
kug-torino
kvision
kweb
lambdaworld_cadiz
lanark
language-evolution
language-proposals
latvia
leakcanary
leedskotlinusergroup
lets-have-fun
libgdx
libkgd
library-development
lincheck
linkeddata
lithuania
london
losangeles
lottie
love
lychee
macedonia
machinelearningbawas
madrid
malaysia
mathematics
meetkotlin
memes
meta
metro-detroit
mexico
miami
micronaut
minnesota
minutest
mirror
mockk
moko
moldova
monsterpuzzle
montreal
moonbean
morocco
motionlayout
mpapt
mu
multiplatform
mumbai
munich
mvikotlin
mvrx
myndocs-oauth2-server
naming
navigation-architecture-component
nepal
new-mexico
new-zealand
newname
nigeria
nodejs
norway
npm-publish
nyc
oceania
ohio-kotlin-users
oldenburg
oolong
opensource
orbit-mvi
osgi
otpisani
package-search
pakistan
panamá
pattern-matching
pbandk
pdx
peru
philippines
phoenix
pinoy
pocketgitclient
polish
popkorn
portugal
practical-functional-programming
proguard
prozis-android-backup
pyhsikal
python
python-contributors
quasar
random
re
react
reaktive
realm
realworldkotlin
reductor
reduks
redux
redux-kotlin
refactoring-to-kotlin
reflect
refreshversions
reports
result
rethink
revolver
rhein-main
rocksdb
romania
room
rpi-pico
rsocket
russian
russian_feed
russian-kotlinasfirst
rx
rxjava
san-diego
science
scotland
scrcast
scrimage
script
scripting
seattle
serialization
server
sg-user-group
singapore
skia-wasm-interop-temp
skrape-it
slovak
snake
sofl-user-group
southafrica
spacemacs
spain
spanish
speaking
spek
spin
splitties
spotify-mobius
spring
spring-security
squarelibraries
stackoverflow
stacks
stayhungrystayfoolish
stdlib
stlouis
strife-discord-lib
strikt
students
stuttgart
sudan
swagger-gradle-codegen
swarm
sweden
swing
swiss-user-group
switzerland
talking-kotlin
tallinn
tampa
teamcity
tegal
tempe
tensorflow
terminal
test
testing
testtestest
texas
tgbotapi
thailand
tornadofx
touchlab-tools
training
tricity-kotlin-user-group
trójmiasto
truth
tunisia
turkey
turkiye
twitter-feed
uae
udacityindia
uk
ukrainian
uniflow
unkonf
uruguay
utah
uuid
vancouver
vankotlin
vertx
videos
vienna
vietnam
vim
vkug
vuejs
web-mpp
webassembly
webrtc
wimix_sentry
wwdc
zircon
Powered by
Title
t

Tyler Rockwood

06/21/2022, 7:18 PM
What is the best forum to submit compiler performance problems? Should I just dump stuff in Youtrack? Our entire backend is written in kotlin (~400 files and around of 80k lines of code) and compilation times have degraded significantly over the last 6 months of kotlinc releases and the increase of code in our repo. As context we use Bazel instead of Gradle as our build system - so there is no incremental compilation, we've been splitting our modules into small pieces to allow for Bazel to do compilation avoidance, but it's still not enough. For some concrete numbers we have a 23 line file that has a single object with one function that takes ~6 seconds to compile. Below is the output of one run when I add the
-Xreport-perf
flag to the compiler run.
info: PERF: <redacted_module_name>, 1 files (23 lines)
info: PERF: INIT: Compiler initialized in 1758 ms
info: PERF:         ANALYZE    4307 ms       5.340 loc/s
info: PERF:  IR TRANSLATION     289 ms      79.585 loc/s
info: PERF:     IR LOWERING     494 ms      46.559 loc/s
info: PERF:   IR GENERATION     348 ms      66.092 loc/s
info: PERF:        GENERATE     842 ms      27.316 loc/s
info: PERF: GC time for G1 Young Generation is 47 ms, 2 collections
info: PERF: GC time for G1 Old Generation is 0 ms, 0 collections
info: PERF: JIT time is 22892 ms
info: PERF: Find Java class performed 11 times, total time 234 ms
info: PERF: Type info performed 39 times, total time 2214 ms
info: PERF: Call resolve performed 38 times, total time 2116 ms
info: PERF: Binary class from Kotlin file performed 210 times, total time 226 ms
We've tried to turn on
-Xbackend-threads
but that fails due to https://youtrack.jetbrains.com/issue/KT-52824. In general we don't have any compiler plugin ourselves, although Bazel uses
jvm-abi-gen
for better compilation avoidance. Are we just hopeless until K2? I've ran across issues like https://youtrack.jetbrains.com/issue/KT-38101 that performance issues (at least in the analyze phase) are being fixed in K2 (which we can't try in alpha yet because of the missing support for plugins). In the release notes for Kotlin 1.7 there was a section that posted performance numbers and there are current packages getting 1-2K loc/s with the current compiler. Even our largest modules (assuming there is some constant overhead that is making the above example so bad) maxes out at about 100 loc/s (5.8k lines in 5 files taking around 57 seconds). Are the Bazel kotlin rules invoking the compiler incorrectly to lead to such bad performance? I'm happy to talk though the threading model and how the Bazel rules invoke the compiler with someone if that turns out to be the issue.
d

dmitriy.novozhilov

06/21/2022, 7:56 PM
It looks like some performance bug inside frontend (most likely in resolution or inference) The best way to report is YouTrack with some reproducer If your project is not open-source and you won't be able to make anonymous reproducer, you can make an issue private and send as many info as possible
t

Tyler Rockwood

06/21/2022, 7:58 PM
Thanks Dmitriy! Is it acceptable to create a Bazel project or would it be better to try and reproduce with raw kotlinc invocations? EDIT: I guess I'm asking which way is more likely to be looked at if you know
👍 1
d

dmitriy.novozhilov

06/21/2022, 8:01 PM
Bazel project will be enough But if you have time and intention to minimize it it will be great help
👍 1
t

Tyler Rockwood

06/21/2022, 8:02 PM
Awesome thanks. I'll try to throw something together this week and post it into YouTrack