Hi, There is not just one cache. It's in another cache, the "queryCache", not the regular row cache. See http://h2database.com/javadoc/org/h2/constant/DbSettings.html?highlight=queryCacheSize&search=queryCache#QUERY_CACHE_SIZE
However, I wonder what data is cached in the query cache. How large are your query statements? Regards, Thomas On Wed, May 8, 2013 at 5:34 PM, <christoff.schm...@finaris.de> wrote: > I did so, but as i see it, that setting does not have any effect for in > memory DBs as I use it. > > > *Cache Settings* > > The database keeps most frequently used data in the main memory. The > amount of memory used for caching can be changed using the setting > CACHE_SIZE. This setting can be set in the database connection URL ( > jdbc:h2:~/test;CACHE_SIZE=131072), or it can be changed at runtime using SET > CACHE_SIZE size. The size of the cache, as represented by CACHE_SIZE is > measured in KB, with each KB being 1024 bytes. *This setting has no > effect for in-memory databases.* For persistent databases, the setting is > stored in the database and re-used when the database is opened the next > time. However, when opening an existing database, the cache size is set to > at most half the amount of memory available for the virtual machine > (Runtime.getRuntime().maxMemory()), even if the cache size setting stored > in the database is larger; however the setting stored in the database is > kept. Setting the cache size in the database URL or explicitly using SET > CACHE_SIZE overrides this value (even if larger than the physical > memory). To get the current used maximum cache size, use the query SELECT > * FROM INFORMATION_SCHEMA.SETTINGS WHERE NAME = 'info.CACHE_MAX_SIZE' > > An experimental scan-resistant cache algorithm "Two Queue" (2Q) is > available. To enable it, append ;CACHE_TYPE=TQ to the database URL. The > cache might not actually improve performance. If you plan to use it, please > run your own test cases first. > > Also included is an experimental second level soft reference cache. Rows > in this cache are only garbage collected on low memory. By default the > second level cache is disabled. To enable it, use the prefix SOFT_. > Example: jdbc:h2:~/test;CACHE_TYPE=SOFT_LRU. The cache might not actually > improve performance. If you plan to use it, please run your own test cases > first. > > To get information about page reads and writes, and the current caching > algorithm in use, call SELECT * FROM INFORMATION_SCHEMA.SETTINGS. The > number of pages read / written is listed. > > > > > Regards, > > Christoff Schmitz > > F I N A R I S > Financial Software Partner GmbH > Sömmerringstrasse 23 > 60322 Frankfurt am Main > > Fon: +49 (0)69 / 254 98 - 24 > Mobile: +49 (0)176 / 206 34 186 > Fax: +49 (0)69 / 254 98 - 50 > eMail: mailto:christoff.schm...@finaris.de<christoff.schm...@finaris.de> > www: http://www.finaris.de und http://www.rapidrep.com > > > > From: Noel Grandin <noelgran...@gmail.com> > To: h2-database@googlegroups.com > Cc: christoff.schm...@finaris.de > Date: 08.05.2013 15:59 > Subject: Re: Memory Usage Problem > ------------------------------ > > > > I could just tell you, but that would deprive you of discovering the > excellent search feature on our website. > > On 2013-05-08 15:22, > *christoff.schm...@finaris.de*<christoff.schm...@finaris.de>wrote: > Hi, > > I use H2 database as embedded database in memory. > The queries processed by the database are quite large, as result my > memory profiler tells me that the *queryCache *(Type * > org.h2.util.SamllLRUCache*) member of an instance of *org.h2.engine.Session > *consumes about 100 MB heap space. > > Is there a possibility to limit that cache size? > > > Regards, > > Christoff Schmitz > > F I N A R I S > Financial Software Partner GmbH > Sömmerringstrasse 23 > 60322 Frankfurt am Main > > Fon: +49 (0)69 / 254 98 - 24 > Mobile: +49 (0)176 / 206 34 186 > Fax: +49 (0)69 / 254 98 - 50 > eMail: *mailto:christoff.schm...@finaris.de*<christoff.schm...@finaris.de> > www: *http://www.finaris.de* <http://www.finaris.de/> und * > http://www.rapidrep.com* <http://www.rapidrep.com/> > > ======================================================= > Disclaimer > The information contained in this e - mail and any attachments > ( together the "message") is intended for the addressee only and may > contain confidential and/or privileged information. 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