[8u] RFR (XS) 8231398: Add time tracing for gc log rotation at safepoint cleanup

[Aleksey Shipilev]

Thanks Paul.

I'll wait for 8u approval now.

-Aleksey

On 9/25/19 7:35 PM, Hohensee, Paul wrote:
> Looks good.
> 
> Paul
> 
> On 9/24/19, 1:17 AM, "hotspot-runtime-dev on behalf of Aleksey Shipilev" <hotspot-runtime-dev-bounces at openjdk.java.net on behalf of shade at redhat.com> wrote:
> 
>     RFE:
>       https://bugs.openjdk.java.net/browse/JDK-8231398
>     
>     There is a nice gotcha when dealing with low latency workloads. The safepoint cleanup does lots of
>     things, notably rotating the GC logs in 8 (fixed by transition to Unified Logging in 9+, see
>     JDK-8145092). Those things are normally caught by -XX:+TraceSafepointCleanupTime, but not gc log
>     rotation, since it misses the tracing statement.
>     
>     We should consider adding the tracing there.
>     
>     Webrev:
>       https://cr.openjdk.java.net/~shade/8231398/webrev.01/
>     
>     Testing: eyeballing safepoint cleanup tracing, tier1 (running)
>     
>     -- 
>     Thanks,
>     -Aleksey
>     
>     
> 


-- 
Thanks,
-Aleksey