private DataBlock GetDataBlockSlow(long lk)
{
// Note that we lock on this, reads on _blockCache could continue
lock (this)
{
if (GetDataBlockFromCache(lk, out var block))
{
return(block);
}
// this method takes time on deserialization which is definitely more that the lock overhead, so uncontended lock is ok
// but should we maybe deserialize twice and dispose on duplication later? TODO review
block = GetBlockFromStorage(lk);
if (block != null)
{
if (!_blockCache.TryAdd(lk, block))
{
ThrowHelper.FailFast("Cannot add block to cache while holding a lock and checking that block was not in the cache.");
}
}
return(block);
}
}
public void WeakReferenceLookup()
{
// How bad is WR lookup
var d = new FastDictionary <long, object>();
// var ds = new DictionarySlim<long, object>();
var lockedWeakDictionary = new LockedWeakDictionary <long>();
var indexedLockedWeakDictionary = new IndexedLockedWeakDictionary <long, Dummy>();
var cd = new ConcurrentDictionary <long, object>();
var wcd = new ConcurrentDictionary <long, WeakReference <object> >();
//var wcd2 = new ConcurrentDictionary<long, WeakReference>();
var wcd3 = new ConcurrentDictionary <long, GCHandle>();
var locker = 0L;
var count = 1_000;
for (int i = 0; i < count; i++)
{
var obj = (object)new Dummy();
d.Add(i, obj);
// ds.GetOrAddValueRef(i) = obj;
cd.TryAdd(i, obj);
wcd.TryAdd(i, new WeakReference <object>(obj));
//wcd2.TryAdd(i, new WeakReference(obj));
var h = GCHandle.Alloc(obj, GCHandleType.Weak);
wcd3.TryAdd(i, h);
lockedWeakDictionary.TryAdd(i, obj);
// lockedWeakDictionary.TryAdd(i, obj);
}
var mult = 100_000;
for (int r = 0; r < 10; r++)
{
//var sum1 = 0.0;
//using (Benchmark.Run("CD", count * mult))
//{
// for (int i = 0; i < count * mult; i++)
// {
// if (cd.TryGetValue(i / mult, out var obj))
// {
// //sum1 += (int)obj;
// }
// else
// {
// Assert.Fail();
// }
// }
//}
//var sum2 = 0.0;
//using (Benchmark.Run("WCD", count * mult))
//{
// // Not so bad, this just needs to save something more in other places
// for (int i = 0; i < count * mult; i++)
// {
// wcd.TryGetValue(i / mult, out var wr);
// if (wr.TryGetTarget(out var tgt))
// {
// //sum2 += (int)tgt;
// }
// else
// {
// Assert.Fail();
// }
// }
//}
//Assert.AreEqual(sum1, sum2);
//var sum4 = 0.0;
//using (Benchmark.Run("WCD2", count * mult))
//{
// // Not so bad, this just needs to save something more in other places
// for (int i = 0; i < count * mult; i++)
// {
// wcd2.TryGetValue(i / mult, out var wr2);
// if (wr2.Target != null)
// {
// sum4 += (int)wr2.Target;
// }
// else
// {
// Assert.Fail();
// }
// }
//}
//Assert.AreEqual(sum1, sum4);
//var sum5 = 0.0;
WCD_H(count, mult, wcd3);
// Assert.AreEqual(sum1, sum5);
//var sum3 = 0.0;
//using (Benchmark.Run("LD", count * mult))
//{
// for (int i = 0; i < count * mult; i++)
// {
// lock (d)
// {
// if (d.TryGetValue(i / mult, out var obj))
// {
// sum3 += (int)obj;
// }
// else
// {
// Assert.Fail();
// }
// }
// }
//}
var sum6 = 0.0;
LWD(count, mult, lockedWeakDictionary);
//var sum7 = 0.0;
//using (Benchmark.Run("ILWD", count * mult))
//{
// for (int i = 0; i < count * mult; i++)
// {
// if (indexedLockedWeakDictionary.TryGetValue(i / mult, out var val))
// {
// //sum7 += (int)val.StorageIndex;
// }
// else
// {
// Assert.Fail();
// }
// }
//}
}
Benchmark.Dump();
Console.WriteLine(d.Count);
}