On 13 Mar 2008, at 15:51, Richard Rodgers wrote: > Hi Simon: > > While I don't doubt for a moment that there are undiscovered memory > leaks in DSpace, I'm not sure I follow the case you describe. By > 'object > cache' I'm guessing you mean the cache that is held by the Context > object. This cache is private to the Context instance, and Contexts > as a rule don't live very long (typically a single HTTP request), so I > don't see how spidering activity could accumulate objects in it.
Fair enough, I guess I didn't correctly understand how the Context object is used. I had assumed that it would be shared across multiple requests, largely because of the existence of the cache. So what happens is, whenever an individual http request accesses an Item, that Item is loaded into the HashMap in the Context, then discarded when the request is completed? Is it the case that an individual Item object is often requested from the database multiple times in the course of a single HTTP request? I'm still curious about the necessity of the cache, as our removing it had no noticeable impact on performance and in fact increased the responsiveness of the site when we did before-and-after tests with Siege. > There are other cases - like ItemImport or MediaFilter runs - that > use a > single context instance (therefore cache) and might iterate over the > whole repository, and *could* suffer from what you describe, but as of > 1.4 at least, these apps were all recoded to flush their caches. Browse.indexAll() and DSIndexer.indexAllItems(), on the other hand, don't seem to flush cache. I appreciate that it's not an often-used case, but it would mean that broken indexes on large databases will probably fail to rebuild due to the cache filling up the heap. -- Simon Brown <[EMAIL PROTECTED]> - Cambridge University Computing Service +44 1223 3 34714 - New Museums Site, Pembroke Street, Cambridge CB2 3QH ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ DSpace-tech mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dspace-tech
