On 06/03/2008, at 12:44 AM, Andrus Adamchik wrote:
This got me thinking about DataRow memory/creation efficiency throughout the framework. We are wasting lots of space on repeating information. Essentially a DataRow for each entity has a well defined set of keys, so ideally we can normalize the storage of DataRows internally, saving an Object[] of values with a reference to a shared "decode map", one per entity. Such a shared map would have DbAttribute names for the keys and array positions for the values. What we'll lose is the ability to serialize DataRows (e.g. for remote notifications), but maybe we can work around it somehow.
How does this interact with the DataDomain snapshot cache? You've explained that this cache is Map<ObjectId, DataRow> but it has an LRU expiry policy. What happens with a DataRow which is expired from the DataDomain but still exists in the 'decode map'? Is it possible to merge the two concepts (snapshot cache and decode map) as long as there was a more sophisticated expiry policy?
The big benefit to reducing memory usage is that users will be able to create larger caches and improve performance.
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