the relationship between metadata size and heap size

[Tom Scavo]

On Mon, Sep 14, 2015 at 4:29 AM, Simon Lundström <simlu at su.se> wrote:
> On Sun, 2015-09-13 at 17:39:20 +0000, Cantor, Scott wrote:
>> On 9/12/15, 10:22 AM, "users on behalf of Tom Scavo" <users-bounces at shibboleth.net on behalf of trscavo at gmail.com> wrote:
>> >
>> >What makes this worse is that the InCommon metadata aggregate will
>> >double in size overnight (literally) once we start importing eduGAIN
>> >metadata. If I knew what to tell deployers to prepare for this event,
>> >I would. Is there some JVM configuration that is known to work with
>> >large aggregates of size 32MB and beyond?
>>
>> […]I don't know why people are having problems (I'm not, with 2.4.x on Java 7/8) and I don't know why it's not logging a simple error if its out of memory, but people are on so many different versions at this point.
>
> Tom, how often do you reload/refresh the metadata? When we refreshed the
> metadata every 10 minutes we ran out of memory every month or so. Our
> federation (SWAMID) metadata is 20MB atm.

InCommon participants are advised to attempt a refresh every hour but
surely some don't and just take the default. This would explain why
some deployments exhibit the issues while others don't.

> This disappeared when we changed it to the default (4h).

Very interesting. Another piece of the puzzle :-)

Thanks Simon.

Tom