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The size of allocation and the size you ask for are not necessarily related. You get the virtual store, but that says nothing about the disk. If you ask for that sort of storage, the usual practice is to try and find big extents. However, this is something we've tinkered with a lot over the years and I can't say exactly how it works today. We have always, however, broken up things that big into littler actual allocations when necessary. In other words, we are under no obligation and never have required ourselves to allocate objects contiguously, nor even on one physical volume. That's why there are ASPs; to allow nearly everything to be on mulitple volumes (with some ability for logical aggregation not tied to physical boundaries). This practice goes all the way back to the beginning of S/38. I would expect, therefore, that something as big as 1 MB may or may not be contiguous. All those kind of ties to contiguous space and physical volumes I always thought was slow, artificial, and confining performance-wise. Single Level Store gave us an excuse to get rid of all that. Really big, contiguous allocations are not as beneficial as one might think, performance-wise. Now, obviously, if we aren't constrained on the initial allocation, neither are we when we extend (make something bigger). We just add new space allocated under very similar rules to creating it originally. Larry W. Loen - Senior Java and iSeries Performance Analyst Dept HP4, Rochester MN +--- | This is the MI Programmers Mailing List! | To submit a new message, send your mail to MI400@midrange.com. | To subscribe to this list send email to MI400-SUB@midrange.com. | To unsubscribe from this list send email to MI400-UNSUB@midrange.com. | Questions should be directed to the list owner/operator: dr2@cssas400.com +---
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