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https://issues.apache.org/jira/browse/CASSANDRA-15766?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17100159#comment-17100159
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Yifan Cai commented on CASSANDRA-15766:
---------------------------------------
There might not be a big difference between multiple and single lambda. The
lambda is compiled into a static method in the bytecode view. If in the hot
path and JIT kicked in, the static method could be even inlined.
Consider the following code
{code:java}
import java.util.function.Supplier;
class Foo {
public void foo() {
comsume(() -> "foo");
}
public void comsume(Supplier<String> supp) {
supp.get();
}
}
{code}
Running {{javap -v -p Foo.class}} reveals the below.
{code:java}
private static java.lang.String lambda$foo$0();
descriptor: ()Ljava/lang/String;
flags: ACC_PRIVATE, ACC_STATIC, ACC_SYNTHETIC
Code:
stack=1, locals=0, args_size=0
0: ldc #5 // String foo
2: areturn
LineNumberTable:
line 5: 0{code}
> NoSpamLogger arguments building objects on hot paths
> ----------------------------------------------------
>
> Key: CASSANDRA-15766
> URL: https://issues.apache.org/jira/browse/CASSANDRA-15766
> Project: Cassandra
> Issue Type: Bug
> Components: Observability/Logging
> Reporter: Jon Meredith
> Assignee: Jon Meredith
> Priority: Normal
> Fix For: 4.0-rc
>
>
> NoSpamLogger is used in hot logging paths to prevent logs being overrun. For
> that to be most effective the arguments to the logger need to be cheap to
> construct. During the internode messaging refactor CASSANDRA-15066,
> performance changes to BufferPool for CASSANDRA-14416
> were accidentally reverted in the merge up from 3.11.
> Reviewing other uses since, it looks like there are a few places where the
> arguments require some form of String building.
> org.apache.cassandra.net.InboundSink#accept
> org.apache.cassandra.net.InboundMessageHandler#processCorruptFrame
> org.apache.cassandra.net.InboundMessageHandler.LargeMessage#deserialize
> org.apache.cassandra.net.OutboundConnection#onOverloaded
> org.apache.cassandra.utils.memory.BufferPool.GlobalPool#allocateMoreChunks
> Formatting arguments should either be precomputed, or if expensive they
> should be computed after the decision on whether to noSpamLog has been made.
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