Concurrent HashSet Class without Blocking<\/p>\n\n\n\n
Updated: July-23,2021<\/p>\n\n\n\n
using System;\nusing System.Collections;\nusing System.Collections.Generic;\nusing System.Diagnostics;\nusing System.Threading;\n[DebuggerDisplay(\"Count = {\" + nameof(Count) + \"}\")]\npublic class CcHashSet<T> : IEnumerable\n{\n private readonly HashSet<T>[] _array;\n private readonly int _size;\n private volatile int[] _activeThreads;\n private volatile int _bP;\n private readonly IEqualityComparer<T> _comparer;\n public volatile int NumberOfActiveThreads;\n public CcHashSet() : this(1024, null)\n {\n }\n public CcHashSet(int size) : this(size, null)\n {\n }\n public CcHashSet(int size, IEqualityComparer<T> comparer)\n {\n if (comparer == null)\n _comparer = EqualityComparer<T>.Default;\n else\n _comparer = comparer;\n ThreadPool.GetMaxThreads(out var nW, out var nI);\n _array = new HashSet<T>[nW];\n _size = size;\n NumberOfActiveThreads = 0;\n _bP = 0;\n _activeThreads = new int[Environment.ProcessorCount];\n _activeThreads.Fill(-1);\n }\n public int Count\n {\n get\n {\n var totalCount = 0;\n for (var i = 0; i < _activeThreads.Length; ++i)\n if (_activeThreads[i] != -1)\n if (_array[_activeThreads[i]] != null)\n totalCount += _array[_activeThreads[i]].Count;\n return totalCount;\n }\n }\n IEnumerator IEnumerable.GetEnumerator()\n {\n return GetEnum();\n }\n public IEnumerator<T> GetEnumerator()\n {\n return GetEnum();\n }\n public void Add(T item)\n {\n var id = Thread.CurrentThread.ManagedThreadId;\n if (_array[id] == null)\n {\n _array[id] = new HashSet<T>(_size, _comparer);\n Interlocked.Increment(ref NumberOfActiveThreads);\n if (_bP >= _activeThreads.Length)\n {\n var nAtA = new int[_activeThreads.Length << 1];\n nAtA.Fill(-1);\n for (var i = 0; i < _activeThreads.Length; ++i)\n if (_activeThreads[i] != -1)\n nAtA[i] = _activeThreads[i];\n _activeThreads = nAtA;\n }\n _activeThreads[_bP] = id;\n Interlocked.Increment(ref _bP);\n }\n if (!Contains(item))\n _array[id].Add(item);\n }\n public bool Contains(T item)\n {\n for (var i = 0; i < _activeThreads.Length; ++i)\n if (_activeThreads[i] != -1)\n if (_array[_activeThreads[i]] != null)\n if (_array[_activeThreads[i]].Contains(item))\n return true;\n return false;\n }\n public IEnumerator<T> GetEnum()\n {\n var arr = ToArray();\n foreach (var i in arr)\n yield return i;\n }\n public T[] ToArray()\n {\n var totalCount = 0;\n for (var i = 0; i < _activeThreads.Length; ++i)\n if (_activeThreads[i] != -1)\n if (_array[_activeThreads[i]] != null)\n totalCount += _array[_activeThreads[i]].Count;\n var ta = new T[totalCount];\n var ptr = 0;\n for (var i = 0; i < _activeThreads.Length; ++i)\n if (_activeThreads[i] != -1)\n if (_array[_activeThreads[i]] != null)\n {\n var it = _array[_activeThreads[i]].ToArray();\n for (var j = 0; j < it.Length; ++j)\n ta[ptr++] = it[j];\n }\n return ta;\n }\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"Concurrent HashSet Class without Blocking Updated: July-23,2021<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[2],"tags":[84,58,207],"_links":{"self":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts\/501"}],"collection":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/comments?post=501"}],"version-history":[{"count":2,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts\/501\/revisions"}],"predecessor-version":[{"id":503,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/posts\/501\/revisions\/503"}],"wp:attachment":[{"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/media?parent=501"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/categories?post=501"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/michaeljohnsteiner.com\/index.php\/wp-json\/wp\/v2\/tags?post=501"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}