/// <summary>
/// Looks up a given key in given shard map.
/// </summary>
/// <param name="shardMap">Storage representation of shard map.</param>
/// <param name="key">Key value.</param>
/// <returns>Mapping corresponding to <paramref name="key"/> or null.</returns>
public virtual ICacheStoreMapping LookupMappingByKey(IStoreShardMap shardMap, ShardKey key)
{
ICacheStoreMapping sm = null;
using (ReadLockScope rls = _cacheRoot.GetReadLockScope(false))
{
CacheShardMap csm = _cacheRoot.LookupById(shardMap.Id);
if (csm != null)
{
using (ReadLockScope rlsShardMap = csm.GetReadLockScope(false))
{
IStoreMapping smDummy;
sm = csm.Mapper.LookupByKey(key, out smDummy);
/*
* // perf counter can not be updated in csm.Mapper.LookupByKey() as this function is also called from csm.Mapper.AddOrUpdate()
* // so updating perf counter value here instead.
* csm.IncrementPerformanceCounter(sm == null ? PerformanceCounterName.MappingsLookupFailedPerSec : PerformanceCounterName.MappingsLookupSucceededPerSec);
*/
}
}
}
return(sm);
}
/// <summary>
/// Removes shard map from cache given the name.
/// </summary>
/// <param name="ssm">Storage representation of shard map.</param>
internal void Remove(IStoreShardMap ssm)
{
if (_shardMapsByName.ContainsKey(ssm.Name))
{
CacheShardMap csm = _shardMapsByName[ssm.Name];
_shardMapsByName.Remove(ssm.Name);
// Dispose off the cached map
if (csm != null)
{
csm.Dispose();
}
}
if (_shardMapsById.ContainsKey(ssm.Id))
{
CacheShardMap csm = _shardMapsById[ssm.Id];
_shardMapsById.Remove(ssm.Id);
// Dispose off the cached map
if (csm != null)
{
csm.Dispose();
}
}
}
/// <summary>
/// Invoked for deleting mapping in cache becase it no longer exists in store.
/// </summary>
/// <param name="mapping">Storage representation of mapping.</param>
public virtual void DeleteMapping(IStoreMapping mapping)
{
using (ReadLockScope rls = _cacheRoot.GetReadLockScope(false))
{
CacheShardMap csm = _cacheRoot.LookupById(mapping.ShardMapId);
if (csm != null)
{
using (WriteLockScope wlscsm = csm.GetWriteLockScope())
{
csm.Mapper.Remove(mapping);
/*
* // Update perf counters for remove mapping operation and mappings count.
* csm.IncrementPerformanceCounter(PerformanceCounterName.MappingsRemovePerSec);
* csm.SetPerformanceCounter(PerformanceCounterName.MappingsCount, csm.Mapper.GetMappingsCount());
*/
Tracer.TraceVerbose(
TraceSourceConstants.ComponentNames.ShardMapManager,
"OnDeleteMapping",
"Cache delete mapping complete. Mapping Id: {0}",
mapping.Id);
}
}
}
}
internal CacheShardMap AddOrUpdate(IStoreShardMap ssm)
{
CacheShardMap csm = new CacheShardMap(ssm);
CacheShardMap csmOldByName = null;
CacheShardMap csmOldById = null;
if (_shardMapsByName.TryGetValue(ssm.Name, out csmOldByName))
{
_shardMapsByName.Remove(ssm.Name);
}
if (_shardMapsById.TryGetValue(ssm.Id, out csmOldById))
{
_shardMapsById.Remove(ssm.Id);
}
// Both should be found or none should be found.
Debug.Assert((csmOldByName == null && csmOldById == null) ||
(csmOldByName != null && csmOldById != null));
// Both should point to same cached copy.
Debug.Assert(Object.ReferenceEquals(csmOldByName, csmOldById));
if (csmOldByName != null)
{
csm.TransferStateFrom(csmOldByName);
// Dispose off the old cached shard map
csmOldByName.Dispose();
}
_shardMapsByName.Add(ssm.Name, csm);
_shardMapsById.Add(ssm.Id, csm);
return(csm);
}
