Quick question about Metaspace verifications (8185034)

Thomas Stüfe thomas.stuefe at gmail.com
Wed Mar 7 06:28:15 UTC 2018

 Hi all,

I am currently working on 8185034 to clean up the metaspace coding a bit,
partially to work off the complexity debt incurred by 8198423.

some quick questions, maybe someone knows:

- We have the metaspace_slow_verify which guards a number of expensive
verifications (I feel a bit arbitrarily). When looking at the history, I
see a change:

changeset:   14474:4154f1817a75 14382:5e86124b835d
user:        mgerdin
date:        Fri Nov 09 00:38:31 2012 +0100
summary:     7200229: NPG: possible performance issue exposed by
Summary: Reduce the amount of calls to ChunkManager verification code
Reviewed-by: jmasa, coleenp

7200229 is a closed bug report, I cannot see it. Any details on this? More
important, should I keep guarding expensive verifications not only with
ASSERT but also with this always-off switch? And if yes, what counts as
expensive? To me, this defies a bit the point of having a debug build.

- Speaking of verifications, I see often verification methods (e.g.
ChunkManager::verify()) which are not guarded by ASSERT - is there a point
to have those functions in release builds? All they do is checking and
asserting, which become no-ops.

Thank you,


More information about the hotspot-runtime-dev mailing list