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From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: Threads [Was: Get real, user and system time]
Date: Tue, 21 Jul 2020 15:46:23 -0400
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On 7/21/2020 12:55 PM, Martin Gregorie wrote:
> On Tue, 21 Jul 2020 08:42:32 -0400, Eric Sosman wrote:
>> This sounds like the "green threads" model used in Old-Time Original
>> Java of a quarter-century ago.  Is Linux still stuck with that relic?
> [...]
> AFAIK Java uses the standard thread module but I could be wrong: I
> haven't examined its inner workings - just know that a running Java
> program looks the same in 'top' as a threaded C program while multiple
> processes with with shared memory look quite different.

     Okay, then: The external evidence ("JVM has only one `top' line")
means that Java isn't using the old "LinuxThreads" implementation, but
we can't really tell whether it is or isn't using "green threads."

>> Anyhow: If you're right, that would explain why nobody runs Java
>> on Linux multi-core servers ...
>>
> More do that you may realise: my mail archive is Java and runs on a dual
> Athlon. I run a variety of Java applications on this Intel i5 based
> laptop. All my computers run Linux apart from one or two PIC-based
> devices (PicAXE and Parallax STAMP) but those don't run Java.

     I guess my intended ironic tone didn't survive transcription onto
Usenet.  Shoulda used a smiley ...

-- 
esosman@comcast-dot-net.invalid
Maskless Trump is a bare-faced liar.
One hundred eighty-three days to go.