RFR: 8229517: Support for optional asynchronous/buffered logging [v21]

[David Holmes]

On 25/05/2021 3:23 pm, Xin Liu wrote:
>> This patch provides a buffer to store asynchrounous messages and flush them to
>> underlying files periodically.
> 
> Xin Liu has updated the pull request incrementally with two additional commits since the last revision:
> 
>   - Remove AsyncLogWriter::flush() from os::shutdown().

You should have waited till there was further discussion on this as 
there needs to be a consensus on what is needed here.

David
-----

>     When jvm aborts, it won't invoke AsyncLogWriter::flush() and guarantee
>     not to hinder the aborting process.
>     
>     Run all unified logging tests in async mode.
>   - Biased to the thread which is taking buffer lock.
> 
> -------------
> 
> Changes:
>    - all: https://git.openjdk.java.net/jdk/pull/3135/files
>    - new: https://git.openjdk.java.net/jdk/pull/3135/files/9800a8cc..2ffc33fe
> 
> Webrevs:
>   - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3135&range=20
>   - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3135&range=19-20
> 
>    Stats: 32 lines in 5 files changed: 7 ins; 15 del; 10 mod
>    Patch: https://git.openjdk.java.net/jdk/pull/3135.diff
>    Fetch: git fetch https://git.openjdk.java.net/jdk pull/3135/head:pull/3135
> 
> PR: https://git.openjdk.java.net/jdk/pull/3135
>