Hi,
I would like to control the way objects are created in response to
ICache.Get() methods.
For instance given a cache defined like this:
ICache<String, MemoryStream> MyCache;
I would like to provide a factory to create the MemoryStream instance when
Ignite needs to create an instance to deserialise a cache entry into, eg:
MyCache = MyGrid.GetOrCreateCache<String, MemoryStream>(new
CacheConfiguration() { cacheItemFactory = new CacheItemFactory<MemoryStream>()
} );
Where:
public class CacheItemFactory<T> where T : new()
{
public T NewCacheItem()
{
return new T();
}
}
Then:
MemoryStream ms = MyCache.Get(“key”)
Will result in my item factory being asked to create the MemoryStream
instance.
This means I can control the creation of objects representing cached items
when they move from the Ignite cache into my local context for access.
I have used MemoryStream as an example of an object type that is relatively
expensive to create in C# and can incur significant GC penalties. There are
others such as cache items that represent arrays of elements etc.
In the MemoryStream case this means I could do something like this to
improve performance and reduce GC interruptions, from
http://adamsitnik.com/Array-Pool/:
public class MyCacheItemFactory<T> where T : new()
{
public T NewCacheItem()
{
return ArrayPool<MemoryStream>.Shared;
}
}
Or even this, from
https://github.com/Microsoft/Microsoft.IO.RecyclableMemoryStream
using Microsoft.IO.RecyclableMemoryStream;
public class MyCacheItemFactory<T> where T : new()
{
static RecyclableMemoryStreamManager manager = new
RecyclableMemoryStreamManager();
public T NewCacheItem()
{
return manager.GetStream();
}
}
For further background on this see http://adamsitnik.com/Array-Pool/
Does this facility already exist in Ignite 2.0, or is on backlog?
I have checked through the CacheConfiguration but have not found this kind
of capability present.
Thanks,
Raymond.
