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Posted to derby-user@db.apache.org by David Zanter <dz...@gmail.com> on 2012/05/17 19:07:31 UTC
Cache Hit/Miss rates for Derby pageCache
Does anyone know, is there a way to get derby statistics from a
running system regarding the hit/miss rates for the Derby Page Cache.
i.e. Statistics that would help determine if the:
derby.storage.pageCacheSize was being effective or needs to be
tweaked.
~David
Re: Cache Hit/Miss rates for Derby pageCache
Posted by Rick Hillegas <ri...@oracle.com>.
On 5/18/12 7:20 AM, Knut Anders Hatlen wrote:
> Mike Matrigali<mi...@sbcglobal.net> writes:
>
>> On 5/17/2012 10:07 AM, David Zanter wrote:
>>> Does anyone know, is there a way to get derby statistics from a
>>> running system regarding the hit/miss rates for the Derby Page Cache.
>>>
>>> i.e. Statistics that would help determine if the:
>>> derby.storage.pageCacheSize was being effective or needs to be
>>> tweaked.
>>>
>>> ~David
>>>
>> cloudscape use to have this functionality, but I don't think it was
>> exposed in derby as it depended on non-standard vti's. Does anyone
>> know if the jmx work provided this functionality.
> I don't think the JMX work exposed any statistics from the engine.
> Another problem is that we only collect statistics in Clock, whereas
> ConcurrentCache, which is the cache implementation we use on Java 5 and
> newer, does not collect any statistics currently.
>
> It would be useful functionality, so it's probably worth filing a JIRA
> issue for it.
>
I've logged DERBY-5772 to track this. Thanks.
Re: Cache Hit/Miss rates for Derby pageCache
Posted by Knut Anders Hatlen <kn...@oracle.com>.
Mike Matrigali <mi...@sbcglobal.net> writes:
> On 5/17/2012 10:07 AM, David Zanter wrote:
>> Does anyone know, is there a way to get derby statistics from a
>> running system regarding the hit/miss rates for the Derby Page Cache.
>>
>> i.e. Statistics that would help determine if the:
>> derby.storage.pageCacheSize was being effective or needs to be
>> tweaked.
>>
>> ~David
>>
> cloudscape use to have this functionality, but I don't think it was
> exposed in derby as it depended on non-standard vti's. Does anyone
> know if the jmx work provided this functionality.
I don't think the JMX work exposed any statistics from the engine.
Another problem is that we only collect statistics in Clock, whereas
ConcurrentCache, which is the cache implementation we use on Java 5 and
newer, does not collect any statistics currently.
It would be useful functionality, so it's probably worth filing a JIRA
issue for it.
--
Knut Anders
Re: Cache Hit/Miss rates for Derby pageCache
Posted by Mike Matrigali <mi...@sbcglobal.net>.
On 5/17/2012 10:07 AM, David Zanter wrote:
> Does anyone know, is there a way to get derby statistics from a
> running system regarding the hit/miss rates for the Derby Page Cache.
>
> i.e. Statistics that would help determine if the:
> derby.storage.pageCacheSize was being effective or needs to be
> tweaked.
>
> ~David
>
cloudscape use to have this functionality, but I don't think it was
exposed in derby as it depended on non-standard vti's. Does anyone
know if the jmx work provided this functionality.