Is this a good implementation of StackExchange Redis pipelining? - asp.net

Question

I'm starting with REDIS and the StackExchange Redis client. I'm wondering if I'm getting the best performance for getting multiple items at once from REDIS.
Situation:
I have an ASP.NET MVC web application that shows a personal calendar on the dashboard of the user. Because the dashboard is the landing page it's heavily used.
To show the calendar items, I first get all calendar item ID's for that particular month:
RedisManager.RedisDb.StringGet("calendaritems_2016_8");
// this returns JSON Serialized List<int>
Then, for each calendar item id I build a list of corresponding cache keys:
"CalendarItemCache_1"
"CalendarItemCache_2"
"CalendarItemCache_3"
etc.
With this collection I reach out to REDIS with a generic function:
var multipleItems = CacheHelper.GetMultiple<CalendarItemCache>(cacheKeys);
That's implemented like:
public List<T> GetMultiple<T>(List<string> keys) where T : class
{
var taskList = new List<Task>();
var returnList = new ConcurrentBag<T>();
foreach (var key in keys)
{
Task<T> stringGetAsync = RedisManager.RedisDb.StringGetAsync(key)
.ContinueWith(task =>
{
if (!string.IsNullOrWhiteSpace(task.Result))
{
var deserializeFromJson = CurrentSerializer.Serializer.DeserializeFromJson<T>(task.Result);
returnList.Add(deserializeFromJson);
return deserializeFromJson;
}
else
{
return null;
}
});
taskList.Add(stringGetAsync);
}
Task[] tasks = taskList.ToArray();
Task.WaitAll(tasks);
return returnList.ToList();
}
Am I implementing pipelining correct? The REDIS CLI monitor shows:
1472728336.718370 [0 127.0.0.1:50335] "GET" "CalendarItemCache_1"
1472728336.718389 [0 127.0.0.1:50335] "GET" "CalendarItemCache_2"
etc.
I'm expecting some kind of MGET command.
Many thanks in advance.

Answer 1

I noticed an overload method for StringGet that accepts a RedisKey[]. Using this, I see a MGET command in the monitor.
public List<T> GetMultiple<T>(List<string> keys) where T : class
{
List<RedisKey> list = new List<RedisKey>(keys.Count);
foreach (var key in keys)
{
list.Add(key);
}
RedisValue[] result = RedisManager.RedisDb.StringGet(list.ToArray());
var redisValues = result.Where(x=>x.HasValue);
var multiple = redisValues.Select(x => DeserializeFromJson<T>(x)).ToList();
return multiple;
}