Redis grain persistence

The Microsoft.Orleans.Persistence.Redis package stores grain state in Redis. The provider uses atomic Redis scripts and ETags to reject stale writes.

Configure a named provider

Configure a provider with AddRedisGrainStorage:

var builder = Host.CreateApplicationBuilder();
builder.UseOrleans(siloBuilder =>
{
    siloBuilder.AddRedisGrainStorage(
        name: "redis",
        configureOptions: options =>
        {
            options.ConfigurationOptions = new ConfigurationOptions
            {
                EndPoints = { "localhost:6379" },
                AbortOnConnectFail = false
            };
        });
});

using var host = builder.Build();

The provider name must match the storage name in [PersistentState].

Configure the default provider

Use AddRedisGrainStorageAsDefault when grains should use Redis without specifying a storage name:

siloBuilder.AddRedisGrainStorageAsDefault(options =>
{
    options.ConfigurationOptions = new ConfigurationOptions
    {
        EndPoints = { "localhost:6379" }
    };
});

Storage behavior

RedisStorageOptions supports:

• ConfigurationOptions for the StackExchange.Redis connection.
• DeleteStateOnClear to delete the Redis key instead of resetting the record.
• EntryExpiry to expire records.
• CreateMultiplexer to supply a shared or custom IConnectionMultiplexer.
• GetStorageKey to customize key generation.
• GrainStorageSerializer to customize the stored representation.

The default key format is {ServiceId}/state/{grainId}/{grainType}.

Warning

Set EntryExpiry only for intentionally ephemeral state, such as tests. Expiration removes state independently of the grain lifecycle and can permit duplicate activations.

Changing the key function or serializer doesn’t migrate existing Redis entries. Plan a data migration or retain compatibility with the previous representation.