public ValueListImpl Read(KeyImpl key)
{
KeyValuePair <TimestampLog, ValueListImpl> val;
Boolean retry = true;
foreach (KeyValueBaseSlaveClient s in slaves.OrderByDescending(a => Guid.NewGuid()))
{
val = s.Read(key);
if (LastLSN.IsBefore(val.Key))
{
LastLSN = val.Key;
retry = false;
break;
}
}
if (retry && masterIsLive)
{
try
{
val = master.Read(key);
}
catch (TimeoutException)
{
masterIsLive = false;
}
}
return(val.Value);
}
public IEnumerable <ValueListImpl> Scan(KeyImpl begin, KeyImpl end, IPredicate <ValueListImpl> predicate)
{
KeyValuePair <TimestampLog, IEnumerable <ValueListImpl> > val;
Boolean retry = true;
foreach (KeyValueBaseSlaveClient s in slaves.OrderByDescending(a => Guid.NewGuid()))
{
try
{
val = s.Scan(begin, end, predicate);
}
catch (TimeoutException)
{
slaves.Remove(s); // Remove slave on timeout
}
if (LastLSN.IsBefore(val.Key))
{
LastLSN = val.Key;
retry = false;
break;
}
}
if (retry)
{
val = master.Scan(begin, end, predicate);
}
return(val.Value);
}
public LogRecord(OperationType operationType, object[] parameters)
{
this.operationType = operationType;
this.parameters = parameters;
lock (LogRecord.lastTimestamp)
{
this.lsn = LogRecord.lastTimestamp.Increment();
}
}
public void Update(KeyImpl key, TimestampLog lsn, ValueListImpl newValues)
{
Object o;
if (!locks.TryGetValue(key, out o))
{
throw new KeyNotFoundException <KeyImpl>(key);
}
lock (o) {
this.Remove(key);
this.Insert(key, lsn, newValues);
}
}
public void Insert(KeyImpl key, TimestampLog lsn, ValueListImpl values)
{
Object o = new Object();
if (!locks.TryAdd(key, o))
{
throw new KeyAlreadyPresentException <KeyImpl>(key);
}
lock (o) {
byte[] data = serializer.ToByteArray(values);
appleStore.Write(nextFree, data);
dict[key] = new AllocRecord(nextFree, data.Length);
timestamps[key] = lsn;
nextFree += data.Length;
return;
}
}
// Assumes that all values of same key are on consecutive lines.
private void LoadIndexFromFile(string serverFilename)
{
int? lastKey = null;
List <int> values = new List <int>();
LogRecord lr = new LogRecord(OperationType.Insert, null);
stamp = lr.Lsn;
using (StreamReader sr = new StreamReader(serverFilename))
{
string line;
while ((line = sr.ReadLine()) != null)
{
if (line.First(c => !whiteSpace.Contains(c)) == '#')
{
continue;
}
string[] parts = line.Split(whiteSpace, StringSplitOptions.RemoveEmptyEntries);
int key = Int32.Parse(parts[0], CultureInfo.InvariantCulture);
int value = Int32.Parse(parts[1], CultureInfo.InvariantCulture);
if (!lastKey.HasValue)
{
lastKey = key;
}
else if (key != lastKey)
{
index.Insert(new KeyImpl(lastKey.Value), new ValueListImpl(values.Select(v => new ValueImpl(v))));
values.Clear();
lastKey = key;
}
values.Add(value);
}
}
}
public void BulkPut(IEnumerable <KeyValuePair <KeyImpl, ValueListImpl> > pairs, TimestampLog lsn)
{
lock (dict) {
foreach (KeyValuePair <KeyImpl, ValueListImpl> pair in pairs)
{
if (dict.ContainsKey(pair.Key))
{
Update(pair.Key, lsn, pair.Value);
}
else
{
Insert(pair.Key, lsn, pair.Value);
}
}
}
}
