Places to potentially find startup performance improvements

[geoand]

Description

• quarkus.uuid provided eagerly -> Produce quarkus.uuid lazily #45434
• application.properties / META-INF/microprofile-config.properties reading from classpath
  • Discussed with @radcortez here
  • Empirically verified that this would make a measurable impact
• ExtLogRecord looking up HostName and Process related data that aren't needed by the default logging pattern
• Offload Vertx / Netty class loading to other thread (like we do for DefaultChannelId)
• Context Propagation config handling -> Use empty default values when building no-op CP instance #45438

These ideas come from looking at this flamegraph

[franz1981]

@geoand I would add #43022 as well
since, with 2 or more event loops, the "new" concurrency allowed by the CL make it load more byte[] and fail on definition later on during class loading. This is both impacting memory and time.

[geoand]

ExtLogRecord looking up HostName and Process related data that aren't needed by the default logging pattern

@dmlloyd I wanted to move the relevant fields into a holder, but the need to support serialization prevents this approach.

[franz1981]

Another "big" (relatively) one @geoand is this -> smallrye/smallrye-common#370

this is very easy: just use 64 bytes cache line as other known projects does i.e. https://github.com/ziglang/zig/blob/master/lib/std/atomic.zig#L429 (which for both arm and x86 uses 2 * 64 bytes due to jbossas/jboss-threads#191)

We are reading from a proc file, in linux, performing both a syscall, parsing and creating garbage for such. It looks an easy win with low impact.

[geoand]

Just for posterity, the comment above should be handled by jbossas/jboss-threads#216

[radcortez]

It also has to be handled here:
https://github.com/smallrye/smallrye-common/blob/e43dfdf9b512185fd8c96ad720fcd4070ff12030/cpu/src/main/java/io/smallrye/common/cpu/CacheInfo.java#L80-L155

I did a quick return with the expected bytes, and on my Mac I noticed around 20 ms improvement in the JVM startup time.

[radcortez]

• ExtLogRecord looking up HostName and Process related data that aren't needed by the default logging pattern

What's the plan with HostName? After #41664, I'm getting 2 / 3 ms increase in the native image startup time.

[geoand]

It also has to be handled here: https://github.com/smallrye/smallrye-common/blob/e43dfdf9b512185fd8c96ad720fcd4070ff12030/cpu/src/main/java/io/smallrye/common/cpu/CacheInfo.java#L80-L155

I did a quick return with the expected bytes, and on my Mac I noticed around 20 ms improvement in the JVM startup time.

With the change from @franz1981, I think that CacheInfo won't be used/loaded at all in Quarkus. Did you see otherwise @radcortez ?

[geoand]

• ExtLogRecord looking up HostName and Process related data that aren't needed by the default logging pattern

What's the plan with HostName? After #41664, I'm getting 2 / 3 ms increase in the native image startup time.

I was hoping @dmlloyd has an idea as my original idea won't work.