Terracotta Discussion Forums (LEGACY READ-ONLY ARCHIVE)

Hello,

I'm using ehcache 2.7.4 with hibernate 3.3.2.
I'd like to use tmc to monitor the cache.
I deploy tmc.war and succesfully connect to the cache.
I set "Polling Interval Seconds" to 1 second.
I perform some operations which use the cache (by inspecting logs I can tell that cache is hit and org.hibernate.SessionFactory.getStatistics().secondLevelCacheHitCount/queryCacheHitCount also prove this).
Tmc however displays information ("Hit Ratio", "Hit Rate", etc) about this fact only for a while, after which all values are set to 0.

Why does it act as described?
How can I change this behaviour to retain non-zero values?

Ehcache.xml (I previously used ehcache 1.2.3)
Code:

 <?xml version="1.0" encoding="UTF-8"?>
 <ehcache updateCheck="false">
 
 
 	<diskStore path="java.io.tmpdir" />
 	<managementRESTService enabled="true" bind="0.0.0.0:9888" />
 
 	<defaultCache maxElementsInMemory="10000" eternal="false"
 		timeToLiveSeconds="120" overflowToDisk="false" diskPersistent="false"
 		diskExpiryThreadIntervalSeconds="120" memoryStoreEvictionPolicy="LRU" />
 
 	<cache name="model.Dictionary"
 		maxElementsInMemory="1300" eternal="false" timeToLiveSeconds="300"
 		overflowToDisk="true" diskPersistent="false"
 		memoryStoreEvictionPolicy="LRU" statistics="true" />
 </ehcache>

Thanks

Hello,
A few ideas :
* can you try to change the polling setting to 5 sec ? and check if the values are not null anymore ?
* can you try, in your browser, to refresh a few time this resource (the Ehcache Rest agent response) :
http://localhost:9888/tc-management-api/agents/cacheManagers/caches/statistics/samples

--> if hitratio or hit rate returning 0 and should not, please tell us and send us your project (or a similar one reproducing the issue if you can't)
Here is what I get locally : http://pastie.org/8372134

* can you try, in your browser to refresh a few time this resource (the TMC Rest Api aggregated response) :
http://localhost:9889/tmc/api/agents/cacheManagers/caches/statistics/samples

--> if hitratio or hit rate returning 0 and should not, please tell us and send us your project (or a similar one reproducing the issue if you can't)
Here is what I get locally : http://www.pastebin.ca/2461167

With those results, I'll be able to determine where your issue is : on the Ehcache Agent side or on the TMC side

Thank you

Hi,
Thanks for the answer.

1. Setting pooling to more than 1 sec causes only zeros to be shown (as opposite to 1 sec, where non-zero values were for a short moment)

2. http://localhost:9889/tc-management-api/agents/cacheManagers/caches/statistics/samples

http://pastebin.ca/2461544

[{"version":null,"agentId":"embedded","name":"org.hibernate.cache.StandardQueryCache","cacheManagerName":"__DEFAULT__","statName":"CacheHitRatio","statValueByTimeMillis":
{"1380785813952":0,"1380785814952":0,"1380785815952":0,"1380785816952":0,"1380785817952":0,"1380785818952":0,"1380785819952":0,"1380785820952":0,"1380785821952":0,"1380785822952":0,
"1380785823972":0,"1380785824952":0,"1380785825952":0,"1380785826952":0,"1380785827952":0,"1380785828952":0,"1380785829952":0,"1380785830952":0,"1380785831952":0,"1380785832952":0,
"1380785833952":0,"1380785834952":0,"1380785835952":0,"1380785836953":0,"1380785837953":0,"1380785838953":0,"1380785839953":0,"1380785840953":100,"1380785841953":0,"1380785842953":0}},{"version":null,"agentId":"embedded","name":"org.hibernate.cache.StandardQueryCache","cacheManagerName":"__DEFAULT__","statName":"CacheHit","statValueByTimeMillis":
{"1380785813952":0,"1380785814952":0,"1380785815952":0,"1380785816952":0,"1380785817952":0,"1380785818952":0,"1380785819952":0,"1380785820952":0,"1380785821952":0,"1380785822952":0,
"1380785823972":0,"1380785824952":0,"1380785825952":0,"1380785826952":0,"1380785827952":0,"1380785828952":0,"1380785829952":0,"1380785830952":0,"1380785831952":0,"1380785832952":0,
"1380785833952":0,"1380785834952":0,"1380785835952":0,"1380785836953":0,"1380785837953":0,"1380785838953":0,"1380785839953":0,"1380785840953":1,"1380785841953":0,"1380785842953":0}},

3. http://localhost:9889/tmc/api/agents/cacheManagers/caches/statistics/samples

http://pastebin.ca/2461547

Here I couldn't find anything

Hello,
those responses you got indicate that there are few hits on the caches.
Did you make sure there is activity wrt the cache ? (frequent get/put)
I'm not talking about hibernate here, the agent will only give you cache activity.
If you're sure the agent did not report proper values, please share a sample project so that we can re run it ourselves and reproduce the issue.
thanks

adahanne wrote:

Hello,
Did you make sure there is activity wrt the cache ? (frequent get/put)
I'm not talking about hibernate here, the agent will only give you cache activity.

I'm not quite sure what do you mean?

adahanne wrote:

please share a sample project so that we can re run it ourselves and reproduce the issue.

Do you also want db schema with dataload script?

hello,
what I mean is that I'd like to make sure that there are hits and misses on your caches before investigating why the ehcache rest agent reported almost no activity.
I think in your case everything's working normally : your app (through hibernate) does not seem to be hitting the caches.
For the reproducible example, I'd like the simplest reproducible test case; so that I'm sure to reproduce it.
thanks

I've written a very simple test where there are 4 items put into the cache and only 1 get, so it's not a frequent activity, but does it matter?

Perhaps I misunderstood how TMC works. I'd expect that this "1" would be displayed till the very end of ehcache running, am I wrong?

hit ratio , hit rate are "live" /dynamic values
don't expect to see anything if nothing is going on

Then all is clear.
Please close the thread.

Thanks for help