Low-Overhead Heap Profiling

Jeremy Manson jeremymanson at google.com
Thu Jun 25 17:34:11 UTC 2015


Why would allocation frequency be more damaging to performance?  Allocation
is cheap, and as long as they become dead before the YG collection, it
costs the same to collect one 1MB object as it does to collection 1000 1K
objects.

Jeremy

On Wed, Jun 24, 2015 at 11:54 PM, Kirk Pepperdine <kirk.pepperdine at gmail.com
> wrote:

>
> But, seriously, why didn’t you like my proposal? It can do anything your
> scheme can with fewer and simpler code changes. The only thing that it
> cannot do is to sample based on object count (i.e., every 100 objects)
> instead of based on object size (i.e., every 1MB of allocations). But I
> think doing sampling based on size is the right approach here (IMHO).
>
>
> I would think that the size based sampling would create a size based bias
> in your sampling. Since IME, it’s allocation frequency is more damaging to
> performance, I’d prefer to see time boxed sampling
>
> Kind regards,
> Kirk Pepperdine
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/attachments/20150625/4e670746/attachment.html>


More information about the hotspot-gc-dev mailing list