static void Main()
{
// This sample shows the use of FASTER as a concurrent pure in-memory cache
var log = new NullDevice(); // no storage involved
// Define settings for log
var logSettings = new LogSettings
{
LogDevice = log, ObjectLogDevice = log,
MutableFraction = 0.9, // 10% of memory log is "read-only region"
CopyReadsToTail = CopyReadsToTail.FromReadOnly, // reads in read-only region are copied to tail
PageSizeBits = 14, // Each page is sized at 2^14 bytes
MemorySizeBits = 25, // (2^25 / 24) = ~1.39M key-value pairs (log uses 24 bytes per KV pair)
};
// Number of records in memory, assuming class keys and values and x64 platform
// (8-byte key + 8-byte value + 8-byte header = 24 bytes per record)
int numRecords = (int)(Math.Pow(2, logSettings.MemorySizeBits) / 24);
// Targeting 1 record per bucket
var numBucketBits = (int)Math.Ceiling(Math.Log2(numRecords));
h = new FasterKV <CacheKey, CacheValue>(1L << numBucketBits, logSettings, comparer: new CacheKey());
sizeTracker = new CacheSizeTracker(h, logSettings.MemorySizeBits);
PopulateStore(numRecords);
ContinuousRandomWorkload();
h.Dispose();
Console.WriteLine("Press <ENTER> to end");
Console.ReadLine();
}
public AddressSpace(Machine m, int addrSpaceShift, int pageShift)
{
this.machine = m;
this.addrSpaceSize = 1 << addrSpaceShift;
this.addrSpaceMask = addrSpaceSize - 1;
this.pageShift = pageShift;
this.pageSize = 1 << pageShift;
this.memoryMap = new IDevice[addrSpaceSize / pageSize];
IDevice nullDev = new NullDevice();
for (int pageno=0; pageno < PageCount; ++pageno)
memoryMap[pageno] = nullDev;
}
public override Maybe<string> Validate()
{
var result = base.Validate();
if (result)
{
if (Streams.Any(s => !s.SampleRate.Equals(SampleRate)))
return Maybe<string>.No("All streams must have the same sample rate as controller.");
if (SampleRate == null)
return Maybe<string>.No("Sample rate required.");
if (SampleRate.BaseUnits.ToLower() != "hz")
return Maybe<string>.No("Sample rate must be in Hz.");
if (SampleRate.QuantityInBaseUnits <= 0)
return Maybe<string>.No("Sample rate must be greater than 0");
if (!ActiveStreams.Any())
return Maybe<string>.No("Must have at least one active stream (a stream with an associated device)");
// This is a workaround for issue #41 (https://github.com/Symphony-DAS/Symphony/issues/41)
foreach (var s in InputStreams)
{
foreach (var ed in s.Devices.OfType<NullDevice>().ToList())
{
s.RemoveDevice(ed);
}
}
if (Math.Max(ActiveOutputStreams.Count(), ActiveInputStreams.Count()) >= 1)
{
var samplingInterval = 1e9m / (SampleRate.QuantityInBaseUnits * Math.Max(ActiveOutputStreams.Count(), ActiveInputStreams.Count()));
while (samplingInterval % Device.DeviceInfo.MinimumSamplingStep != 0m)
{
var inactive = InputStreams.Where(s => !s.Active).ToList();
if (!inactive.Any())
return Maybe<string>.No("A well-aligned sampling interval is not possible with the current sampling rate");
var dev = new NullDevice();
dev.BindStream(inactive.First());
samplingInterval = 1e9m / (SampleRate.QuantityInBaseUnits * Math.Max(ActiveOutputStreams.Count(), ActiveInputStreams.Count()));
}
}
}
return result;
}
