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Greetings all! I have project with structure simil...
# gradle
n
Greetings all! I have project with structure similar to nowinandroid Why I see 2 java processes while executing gradle commands? And is it possible to limit memory consumption of second java process? • Second stays in the limits set from root 
gradle.properties
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'org.gradle.jvmargs=-Xmx3072m -XX:+UseParallelGC -Dfile.encoding=UTF-8'
• First one takes way more, usually around 4,5Gb
s
I don't know how Kotlin-specific this question is, so this might not be the best place to ask. What gradle commands are you running? Maybe the second process is for running tests, or something like that.
n
Sorry if this is not right place to ask, I was just thinking maybe it’s some kind of kotlin daemon running along with gradle daemon I’m running unit tests with
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./gradlew clean koverVerify --no-build-cache --no-daemon
s
There will almost certainly be some extra processes. I think the Kotlin compiler often runs in a daemon. Tests will also probably fork extra processes. And Gradle itself will almost always make a separate daemon process, even if you specify 
--no-daemon
.
If you can, I'd say just rely on swap and let the build do whatever it wants. I've had to try to limit builds to a fixed amount of memory in the past and it's a massive pain.
n
--no-daemon
I’ve added just for testing, so I don’t need to stop gradle before my test run When I ran 
assemble
result is roughly the same The reason I want to limit it because on CI (14GB RAM) my builds are failing sometimes with OOM, and I suspect this unlimited process may consume too much memory
s
Yeah, I've been there. I have no idea why 1️⃣ CI servers increasingly seem to have less memory than developer machines and 2️⃣ CI servers never seem to have any kind of swap 😢
Decades ago we invented memory virtualisation so we wouldn't have to deal with this, and then along comes container orchestration with its fancy ideas about how every process needs a fixed amount of memory again
It's like we went back in time
Sorry, I guess that touched a nerve 😂
I don't have a solution for you 😞
n
I appreciate it anyway! Our devops initially proposed to have 4GB servers for our builds 😂
🤦 1
c
what do you set the java option for memory to? there are also other gradle options you can set on your.
On Circle CI I usually use
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JAVA_TOOL_OPTIONS: "-Xmx3G"
GRADLE_OPTS: "-Dorg.gradle.daemon=false -Dorg.gradle.parallel=false -Dorg.gradle.workers.max=2 -Dkotlin.compiler.execution.strategy=in-process -Dkotlin.incremental=false"
and my builds run on a large resource class with 8GB of ram.
t
Why I see 2 java processes while executing gradle commands? And is it possible to limit memory consumption of second java process?
Second process is Kotlin daemon. You could define jvm args for it via 
kotlin.daemon.jvmargs
Gradle property
n
It was indeed kotlin daemon, thank you for help! This one worked for me:
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-Dkotlin.daemon.jvm.options=-Xmx3G
I’ve noticed that settings for a Kotlin daemon like:
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kotlin.daemon.jvmargs=-Xmx4G -Xms2G
are not honored if gradle daemon was enabled and works perfectly otherwise. Does anyone have any ideas as to why?
t
Gradle daemon is always starting even if you pass 
--no-daemon
option. Why do you think it is not honored? cc @Alexander.Likhachev
a
> I’ve noticed that settings for a Kotlin daemon like: >
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kotlin.daemon.jvmargs=-Xmx4G -Xms2G
> are not honored if gradle daemon was enabled and works perfectly otherwise Hm, could you explain it more or maybe even provide a reproducer project, please? In some cases, the Kotlin daemon may reuse the daemon process that was started earlier. It has special handling for the case e.g. if you request 2GB, but there’s already a daemon started for another project that requested 5GB. Then, instead of starting 2 daemons the daemon with the biggest memory limit will be reused. It’s not yet properly documented and sometimes may work not as expected, we have plans to improve this. Thus, if you’re experimenting with different memory limits, sometimes you have to kill the daemon (or use 
--no-daemon
) during the experiments.
n
Before tests I always do 
gradle --stop
. I was probably misinterpreting output of 
top -o mem
command. I’m not sure then what the column 
mem
shows in this case.
a
mem
in the output of 
top
shows the physical memory currently allocated by OS to the JVM process. Could you provide more specific details about the output you are seeing? Is it lesser than you’re setting? Bigger? You may be also interested in more specialized tools for JVM like 
jcmd <pid> GC.heap_info
, 
jcmd <pid> VM.flags
where you can find the required process id using the 
jps
tool. Or you may even use visual tools like VisualVM or the one included into IDEA Ultmate By setting 
-Xmx
, you’re limiting only the heap memory of JVM, it does not say anything about the JVM non-heap memory as well as the metaspace
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