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LRU Image Cache Cleanup Service

This is part of the service related image preview and retrieval from SRB. This functionality was for early MBIRN and might be easily upgraded for other usage scenarios. However, currently it is not adopted for fBIRN usage.

To increase response time under heavy load, a least recently used (LRU) file cache is used in the middle tier server. The active class FileCacheCleanupService coordinates LRU file cache mechanism by using external Perl scripts for the cache eviction etc. To assure proper concurrent operation, during image series retrieval from SRB and DICOM to AFNI conversion, exclusive file locks are used. To avoid race conditions during data streaming and cache cleanup, a read/write lock mechanism is simulated with file locks. The cache eviction is based both on file age and size.



Burak Ozyurt 2008-03-28