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POMemory usage, SortedList vs List problem
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copied!<p>I was using SortedList() in a class which stores about 15-100K data.</p> <p>Recently my requirements changed, data should not be stored as sorted any more so I switched to List().</p> <p>However in this case I noticed that List() consumes about 20%+ more memory.</p> <p><strong>9K items:</strong> </p> <ul> <li>SortedList: 105MB</li> <li>List: 125MB</li> </ul> <p><strong>15K items:</strong> </p> <ul> <li>SortedList: 115MB</li> <li>List: 140MB</li> </ul> <p>In the environment I develop, memory is quite crucial. Instead of List() what can I use to avoid this extra memory consumption and still have a non-sorted list?</p> <p><em>P.S. I do use a HashSet(Of String) to provide uniqueness check while using List(Of) to simulate SortedList.ContainsKey() although I don't think it can bring such memory overhead.</em></p> <p><em>P.S. 2: My app has got about 80 MB base memory allocation in the startup. So numbers should read as 105-80=25, 125-80 =45 and so on</em></p> <p><strong>RESULTS</strong></p> <p>Thanks for the all answers, final results are:</p> <ul> <li>You should set the correct capacity to save memory</li> <li>Hashset is very bad about memory, and consumes way more than expectations. This was the problem. Somehow SortedList() manages to use less memory for a similar functionality.</li> </ul> <p><strong>Some Bencmarks:</strong> 500 chars, 250000 insert</p> <p><strong>List(OF STring)(50000)</strong></p> <p>274 ms - 226 MB</p> <p><strong>SortedList(Of String, String)(50000)</strong></p> <p>34868 ms - 230 Mb</p> <p><strong>Hashset</strong></p> <p>420 ms - 232 MB</p> <p><strong>Dictionary(OF String, Object)</strong></p> <p>486 ms - 234 MB</p> <p>Although when I changed decreased count to 25, then:</p> <p><strong>Hashset</strong> for 600.000 iteration 300 Mb where <strong>List()</strong> is 286 Mb</p> <p>Also about Hashset memory usage: <a href="http://blog.mischel.com/2008/04/09/hashset-limitations/" rel="nofollow noreferrer">http://blog.mischel.com/2008/04/09/hashset-limitations/</a> Dictionary(Of string, object) was not much better either in my test.</p>

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