Redis Redis/Memory RemoveAll repro

main.cs

using System;
using ServiceStack;
using ServiceStack.Text;
using ServiceStack.Redis;
using ServiceStack.DataAnnotations;
using ServiceStack.Caching;

var redisManager = new RedisManagerPool("localhost:6379");
var redis = redisManager.GetClient();
redis.FlushAll();

var cache = redisManager.GetCacheClient().WithPrefix("sample");
var memCache = new MemoryCacheClient().WithPrefix("sample");

cache.Set("siafracc_QUERY_Deposit__Query_Deposit_10_1", "A");
cache.Set("siafracc_QUERY_Deposit__0_1___CUSTOM", "B");

memCache.Set("siafracc_QUERY_Deposit__Query_Deposit_10_1", "A");
memCache.Set("siafracc_QUERY_Deposit__0_1___CUSTOM", "B");

var keys = cache.GetKeysStartingWith("siafracc_QUERY_Deposit");
var memKeys = memCache.GetKeysStartingWith("siafracc_QUERY_Deposit");

cache.RemoveAll(keys);
memCache.RemoveAll(memKeys);

var newKeys = cache.GetKeysStartingWith("siafracc_QUERY_Deposit");
var memNewKeys = memCache.GetKeysStartingWith("siafracc_QUERY_Deposit");

"oldKeys:".Print();
keys.PrintDump();

"newKeys:".Print();
newKeys.PrintDump();

"memNewKeys:".Print();
memNewKeys.PrintDump();

packages.config

<?xml version="1.0" encoding="utf-8"?>
<packages>
  <package id="System.Memory" version="4.5.4" targetFramework="net45" />
  <package id="ServiceStack.Text" version="5.9.0" targetFramework="net45" />
  <package id="ServiceStack.Client" version="5.9.0" targetFramework="net45" />
  <package id="ServiceStack.Interfaces" version="5.9.0" targetFramework="net45" />
  <package id="ServiceStack.Redis" version="5.9.0" targetFramework="net45" />
  <package id="ServiceStack" version="5.9.0" targetFramework="net45" />
</packages>