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  • C#开源磁盘/内存缓存引擎

    前言

    昨天写了个 《基于STSdb和fastJson的磁盘/内存缓存》,大家可以先看看。下午用到业务系统时候,觉得可以改进一下,昨晚想了一个晚上,刚才重新实现一下。

    更新

    1. 增加了对批量处理的支持,写操作速度提升5倍,读操作提升100倍

    2. 增加了一个存储provider,可以选择不用STSdb做存储,而用物理文件/Dictionary。

    3. 增加了空间回收

    4. 增加了对并发的支持

    需求

    业务系统用的是数据库,数据量大,部分只读或相对稳定业务查询复杂,每次页面加载都要花耗不少时间(不讨论异步),觉得可以做一下高速缓存,譬如用nosql那种key/value快速存取结果

    目的

    提供一个简单易用的解决缓存方案,可以根据数据的大小缓存到内存或者磁盘。

    实现

    存取

    方法1. 基于STSdb,提供高效的Key/Value存取,支持磁盘/内存,对Key无限制

    方法2. 基于直接物理文件/Dictionary。Key必须是基本类型,譬如int/long/uint/ulong/DateTime/string等。

    代码

    代码比较简单,花了2个小时写的,很多情况没考虑,譬如磁盘空间/内存不足,自动回收过期缓存等,这些留给大家做家庭作业吧。另外,为了发布方便,STSdb和fastJson的代码都合并到一个项目里。

    BaseCahce.cs

    这是一个抽象基类,提供存取接口。

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    
    namespace Com.SuperCache.Engine
    {
        public abstract class BaseCache
        {
            protected internal const string KeyExpiration = "Expiration";
    
            public abstract void Add<K>(string Category, K Key, object Data);
            public abstract void Add<K, V>(string Category, IEnumerable<KeyValuePair<K, V>> Items, DateTime? ExpirationDate);
            public abstract void Add<K>(string Category, K Key, object Data, DateTime? ExpirationDate);
            public abstract List<KeyValuePair<K, V>> Get<K, V>(string Category, IEnumerable<K> Keys);
            public abstract V Get<K, V>(string Category, K Key);
            public abstract void Recycle<K>( string Category, long Count);
        }
    }
    

      

      

    CahceEngine.cs

    主要调用缓存引擎

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using STSdb4.Database;
    using fastJSON;
    using System.IO;
    
    namespace Com.SuperCache.Engine
    {
        public enum CacheProviders
        {
            Default = 1,
            Raw = 2
        }
    
        public enum RecycleAlgorithms
        {
            None = 0,
            //LRU = 1,
            MRU = 2
        }
    
        public enum RecycleModes
        {
            None = 0,
            Passive = 1,
            Active = 2
        }
    
        public class CacheEngine
        {
            private BaseCache cacheProvider = null;
    
            public CacheEngine(string DataPath)
                : this(CacheProviders.Default, DataPath, RecycleAlgorithms.None, 0, 0, RecycleModes.None)
            {
            }
    
            public CacheEngine(CacheProviders Provider, string DataPath, RecycleAlgorithms RecycleAlgorithm, int MaxCount, int Threshold, RecycleModes RecycleMode)
            {
                switch (Provider)
                {
                    case CacheProviders.Default:
                        cacheProvider = new STSdbCache(DataPath, RecycleAlgorithm, MaxCount, Threshold, RecycleMode);
                        break;
                    case CacheProviders.Raw:
                        cacheProvider = new RawCache(DataPath, RecycleAlgorithm, MaxCount, Threshold, RecycleMode);
                        break;
                    default:
                        break;
                }
            }
    
            public void Add<K>(string Category, K Key, object Data)
            {
                cacheProvider.Add<K>(Category, Key, Data);
            }
    
            public void Add<K, V>(string Category, IEnumerable<KeyValuePair<K, V>> Items, DateTime? ExpirationDate)
            {
                cacheProvider.Add<K, V>(Category, Items, ExpirationDate);
            }
    
            public void Add<K>(string Category, K Key, object Data, DateTime? ExpirationDate)
            {
                cacheProvider.Add<K>(Category, Key, Data, ExpirationDate);
            }
    
            public List<KeyValuePair<K, V>> Get<K, V>(string Category, IEnumerable<K> Keys)
            {
                return cacheProvider.Get<K, V>(Category, Keys);
            }
    
            public V Get<K, V>(string Category, K Key)
            {
                return cacheProvider.Get<K, V>(Category, Key);
            }
    
        }
    }
    

      

      

      

    STSdbCache.cs

    STSdb存储引擎  

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using STSdb4.Database;
    using fastJSON;
    using System.IO;
    
    namespace Com.SuperCache.Engine
    {
        public class STSdbCache : BaseCache
        {
            private const string UsageStat = "SuperCacheUsageStat";
            private string dataPath;
            private static IStorageEngine memoryInstance = null;
            private static object syncRoot = new object();
            private bool isMemory = false;
            private RecycleAlgorithms recycleAlgorithm;
            private int maxCount;
            private int threshold;
            private RecycleModes recycleMode;
    
            public STSdbCache(string DataPath, RecycleAlgorithms RecycleAlgorithm, int MaxCount, int Threshold, RecycleModes RecycleMode)
            {
                dataPath = DataPath;
                if (!dataPath.EndsWith(Path.DirectorySeparatorChar.ToString()))
                    dataPath += Path.DirectorySeparatorChar;
    
                isMemory = string.IsNullOrEmpty(DataPath);
    
                recycleAlgorithm = RecycleAlgorithm;
                maxCount = MaxCount;
                threshold = Threshold;
                recycleMode = RecycleMode;
            }
    
            public override void Add<K>(string Category, K Key, object Data)
            {
                Add(Category, Key, Data, null);
            }
    
            private IStorageEngine Engine
            {
                get
                {
                    if (isMemory)
                    {
                        lock (syncRoot)
                        {
                            if (memoryInstance == null)
                                memoryInstance = STSdb.FromMemory();
                        }
                        return memoryInstance;
                    }
                    else
                        return STSdb.FromFile(GetFile(false), GetFile(true));
                }
            }
    
            private string GetExpirationTable(string Category)
            {
                return KeyExpiration + "_" + Category;
            }
    
            public override void Add<K, V>(string Category, IEnumerable<KeyValuePair<K, V>> Items, DateTime? ExpirationDate)
            {
                long count = 0;
    
                lock (syncRoot)
                {
                    var engine = Engine;
                    var table = engine.OpenXIndex<K, string>(Category);
                    var expiration = engine.OpenXIndex<K, DateTime>(GetExpirationTable(Category));
    
                    //track recycle
                    IIndex<K, int> usage = null;
                    if (recycleAlgorithm != RecycleAlgorithms.None)
                        usage = engine.OpenXIndex<K, int>(UsageStat);
    
                    Items.ForEach(i =>
                        {
                            var key = i.Key;
                            var data = i.Value;
                            //will only serialize object other than string
                            var result = typeof(V) == typeof(string) ? data as string : JSON.Instance.ToJSON(data);
                            table[key] = result;
                            table.Flush();
    
                            //specify expiration
                            //default 30 mins to expire from now
                            var expirationDate = ExpirationDate == null || ExpirationDate <= DateTime.Now ? DateTime.Now.AddMinutes(30) : (DateTime)ExpirationDate;
                            expiration[key] = expirationDate;
                            expiration.Flush();
    
                            //track recycle
                            if (usage != null)
                            {
                                usage[key] = 0;
                                if (recycleMode == RecycleModes.Active)
                                    Recycle<K>(Category, usage.Count());
                            }
                        });
    
                    if (usage != null)
                        count = usage.Count();
    
                    engine.Commit();
    
                    //only dispose disk-based engine
                    if (!isMemory)
                        engine.Dispose();
                }
    
                if (recycleMode == RecycleModes.Passive)
                    Recycle<K>(Category, count);
            }
    
            public override void Add<K>(string Category, K Key, object Data, DateTime? ExpirationDate)
            {
                Add<K, object>(Category, new List<KeyValuePair<K, object>> { new KeyValuePair<K, object>(Key, Data) }, ExpirationDate);
            }
    
            private string GetFile(bool IsData)
            {
                if (!Directory.Exists(dataPath))
                    Directory.CreateDirectory(dataPath);
                return dataPath + "SuperCache." + (IsData ? "dat" : "sys");
            }
    
            public override List<KeyValuePair<K, V>> Get<K, V>(string Category, IEnumerable<K> Keys)
            {
                var result = new List<KeyValuePair<K, V>>();
                lock (syncRoot)
                {
                    var engine = Engine;
                    var table = engine.OpenXIndex<K, string>(Category);
                    var expiration = engine.OpenXIndex<K, DateTime>(GetExpirationTable(Category));
                    var isCommitRequired = false;
    
                    //track recycle
                    IIndex<K, int> usage = null;
                    if (recycleAlgorithm != RecycleAlgorithms.None)
                        usage = engine.OpenXIndex<K, int>(UsageStat);
    
                    Keys.ForEach(key =>
                        {
                            string buffer;
                            V value;
                            if (table.TryGet(key, out buffer))
                            {
                                //will only deserialize object other than string
                                value = typeof(V) == typeof(string) ? (V)(object)buffer : JSON.Instance.ToObject<V>(buffer);
                                bool needUpdate = true;
                                DateTime expirationDate;
                                //get expiration date
                                if (expiration.TryGet(key, out expirationDate))
                                {
                                    //expired
                                    if (expirationDate < DateTime.Now)
                                    {
                                        value = default(V);
                                        table.Delete(key);
                                        table.Flush();
                                        expiration.Delete(key);
                                        expiration.Flush();
                                        isCommitRequired = true;
                                        needUpdate = false;
                                    }
                                }
    
                                //track recycle
                                if (usage != null && needUpdate)
                                {
                                    usage[key]++;
                                    isCommitRequired = true;
                                }
                            }
                            else
                                value = default(V);
    
                            result.Add(new KeyValuePair<K, V>(key, value));
                        });
    
                    //only need to commit write actions
                    if (isCommitRequired)
                        engine.Commit();
    
                    //only dispose disk-based engine
                    if (!isMemory)
                        engine.Dispose();
                }
                return result;
            }
    
            public override V Get<K, V>(string Category, K Key)
            {
                var buffer = Get<K, V>(Category, new K[] { Key });
                var result = buffer.FirstOrDefault();
                return result.Value;
            }
    
            public override void Recycle<K>(string Category, long Count)
            {
                if (Count < maxCount)
                    return;
    
                switch (recycleAlgorithm)
                {
                    case RecycleAlgorithms.MRU:
                        lock (syncRoot)
                        {
                            var engine = Engine;
                            var table = engine.OpenXIndex<K, string>(Category);
                            var expiration = engine.OpenXIndex<K, DateTime>(GetExpirationTable(Category));
                            var usage = engine.OpenXIndex<K, int>(UsageStat);
                            //find out expired items
                            var expired = expiration.Where(e => e.Value < DateTime.Now);
                            expired.ForEach(e =>
                                {
                                    table.Delete(e.Key);
                                    expiration.Delete(e.Key);
                                    usage.Delete(e.Key);
                                });
    
                            //find out least used items
                            var leastUsed = usage.OrderByDescending(s => s.Value).Skip(maxCount - threshold);
                            leastUsed.ForEach(u =>
                            {
                                table.Delete(u.Key);
                                expiration.Delete(u.Key);
                                usage.Delete(u.Key);
                            });
    
                            table.Flush();
                            expiration.Flush();
                            usage.Flush();
                            engine.Commit();
    
                            if (!isMemory)
                                engine.Dispose();
                        }
                        break;
                    default:
                        break;
                }
            }
        }
    }
    

      

      

    RawCache.cs

    物理文件/Dictionary引擎

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using STSdb4.Database;
    using fastJSON;
    using System.IO;
    
    namespace Com.SuperCache.Engine
    {
        public class RawCache : BaseCache
        {
            private const string ExpirationFileExtension = "exp";
            private const string DataFileExtension = "dat";
            private const string statFile = "SuperCache.sta";
            private string dataPath;
            private static Dictionary<string, object> memoryData = new Dictionary<string, object>();
            private static Dictionary<string, DateTime?> memoryExpiration = new Dictionary<string, DateTime?>();
            private static object syncRoot = new object();
            private bool isMemory = false;
            private RecycleAlgorithms recycleAlgorithm;
            private int maxCount;
            private int threshold;
            private static Dictionary<string, KeyValue> usageStat = new Dictionary<string, KeyValue>();
            private Dictionary<string, KeyValuePair<DateTime, string>> expiredFiles = new Dictionary<string, KeyValuePair<DateTime, string>>();
            private RecycleModes recycleMode;
    
            public RawCache(string DataPath, RecycleAlgorithms RecycleAlgorithm, int MaxCount, int Threshold, RecycleModes RecycleMode)
            {
                dataPath = DataPath;
                if (!dataPath.EndsWith(Path.DirectorySeparatorChar.ToString()))
                    dataPath += Path.DirectorySeparatorChar;
    
                isMemory = string.IsNullOrEmpty(DataPath);
    
                recycleAlgorithm = RecycleAlgorithm;
                maxCount = MaxCount;
                threshold = Threshold;
                recycleMode = RecycleMode;
            }
    
            public override void Add<K>(string Category, K Key, object Data)
            {
                Add(Category, Key, Data, null);
            }
    
            private string GetExpirationTable(string Category)
            {
                return KeyExpiration + "_" + Category;
            }
    
            public override void Add<K, V>(string Category, IEnumerable<KeyValuePair<K, V>> Items, DateTime? ExpirationDate)
            {
                long count = 0;
    
                lock (syncRoot)
                {
                    Items.ForEach(i =>
                        {
                            var key = i.Key;
                            var data = i.Value;
                            var cacheKey = GetKey(Category, key.ToString());
    
                            if (isMemory)
                            {
                                memoryData[cacheKey] = data;
                                memoryExpiration[cacheKey] = ExpirationDate;
    
                                //recycle algo
                                switch (recycleAlgorithm)
                                {
                                    case RecycleAlgorithms.MRU:
                                        usageStat[cacheKey] = new KeyValue(string.Empty, 0);
                                        if (recycleMode == RecycleModes.Active)
                                            Recycle<K>(Category, memoryData.Count);
                                        break;
                                    default:
                                        break;
                                }
                            }
                            else
                            {
                                //will only serialize object other than string
                                var result = typeof(V) == typeof(string) ? data as string : JSON.Instance.ToJSON(data);
                                var fileKey = key.ToString();
                                var dataFile = GetFile(Category, fileKey, true);
                                bool exists = File.Exists(dataFile);
                                File.WriteAllText(dataFile, result);
    
                                //specify expiration
                                //default 30 mins to expire from now
                                var expirationDate = ExpirationDate == null || ExpirationDate <= DateTime.Now ? DateTime.Now.AddMinutes(30) : (DateTime)ExpirationDate;
                                var expirationFile = GetFile(Category, fileKey, false);
                                File.WriteAllText(expirationFile, expirationDate.ToString());
    
                                //recycle algo
                                if (recycleAlgorithm != RecycleAlgorithms.None)
                                {
                                    var statFilePath = dataPath + statFile;
                                    if (File.Exists(statFilePath))
                                    {
                                        var buffer = File.ReadAllText(statFilePath);
                                        count = Convert.ToInt32(buffer);
                                    }
                                    if (!exists)
                                    {
                                        count++;
                                        File.WriteAllText(statFilePath, count.ToString());
                                    }
                                    switch (recycleAlgorithm)
                                    {
                                        case RecycleAlgorithms.MRU:
                                            usageStat[cacheKey] = new KeyValue(expirationFile, 0);
                                            expiredFiles[cacheKey] = new KeyValuePair<DateTime, string>(expirationDate, expirationFile);
                                            if (recycleMode == RecycleModes.Active)
                                                Recycle<K>(Category, count);
                                            break;
                                        default:
                                            break;
                                    }
                                }
                            }
                        });
    
                    if (recycleAlgorithm != RecycleAlgorithms.None && recycleMode == RecycleModes.Passive)
                    {
                        if (isMemory)
                            count = memoryData.Count;
                        Recycle<K>(Category, count);
                    }
                }
            }
    
            public override void Add<K>(string Category, K Key, object Data, DateTime? ExpirationDate)
            {
                Add<K, object>(Category, new List<KeyValuePair<K, object>> { new KeyValuePair<K, object>(Key, Data) }, ExpirationDate);
            }
    
            private string GetFile(string Category, string FileName, bool IsData)
            {
                var path = dataPath + Category.NormalizeFileName() + @"";
                if (!Directory.Exists(path))
                    Directory.CreateDirectory(path);
                return path + FileName.NormalizeFileName() + "." + (IsData ? "dat" : ExpirationFileExtension);
            }
    
            private string GetKey(string Category, string Key)
            {
                return Category + "_" + Key;
            }
    
            public override List<KeyValuePair<K, V>> Get<K, V>(string Category, IEnumerable<K> Keys)
            {
                var result = new List<KeyValuePair<K, V>>();
                lock (syncRoot)
                {
                    Keys.ForEach(key =>
                        {
                            string buffer;
                            V value;
                            var cacheKey = GetKey(Category, key.ToString());
                            if (isMemory)
                            {
                                object memBuffer;
                                if (memoryData.TryGetValue(cacheKey, out memBuffer))
                                {
                                    //track recycle
                                    switch (recycleAlgorithm)
                                    {
                                        case RecycleAlgorithms.MRU:
                                            usageStat[cacheKey].Value++;
                                            break;
                                        default:
                                            break;
                                    }
    
                                    value = (V)memBuffer;
                                    DateTime? expirationDate;
                                    if (memoryExpiration.TryGetValue(cacheKey, out expirationDate))
                                    {
                                        //expired
                                        if (expirationDate != null && (DateTime)expirationDate < DateTime.Now)
                                        {
                                            value = default(V);
                                            memoryData.Remove(cacheKey);
                                            memoryExpiration.Remove(cacheKey);
                                        }
                                    }
                                }
                                else
                                    value = default(V);
                            }
                            else
                            {
                                var dataFilePath = GetFile(Category, key.ToString(), true);
                                if (File.Exists(dataFilePath))
                                {
                                    buffer = File.ReadAllText(dataFilePath);
    
                                    //track recycle
                                    switch (recycleAlgorithm)
                                    {
                                        case RecycleAlgorithms.MRU:
                                            usageStat[cacheKey].Value++;
                                            break;
                                        default:
                                            break;
                                    }
    
                                    //will only deserialize object other than string
                                    value = typeof(V) == typeof(string) ? (V)(object)buffer : JSON.Instance.ToObject<V>(buffer);
                                    DateTime expirationDate;
                                    var expirationFilePath = GetFile(Category, key.ToString(), false);
                                    if (File.Exists(expirationFilePath))
                                    {
                                        buffer = File.ReadAllText(expirationFilePath);
                                        expirationDate = Convert.ToDateTime(buffer);
                                        //expired
                                        if (expirationDate < DateTime.Now)
                                        {
                                            value = default(V);
                                            File.Delete(dataFilePath);
                                            File.Delete(expirationFilePath);
                                        }
                                    }
                                }
                                else
                                    value = default(V);
                            }
    
                            result.Add(new KeyValuePair<K, V>(key, value));
                        });
                }
                return result;
            }
    
            public override V Get<K, V>(string Category, K Key)
            {
                var buffer = Get<K, V>(Category, new K[] { Key });
                var result = buffer.FirstOrDefault();
                return result.Value;
            }
    
            public override void Recycle<K>(string Category, long Count)
            {
                if (Count < maxCount)
                    return;
    
                switch (recycleAlgorithm)
                {
                    case RecycleAlgorithms.MRU:
                        lock (syncRoot)
                        {
                            var recycledFileCount = 0;
    
                            if (isMemory)
                            {
                                //find out expired items
                                var memExpired = memoryExpiration.Where(e => e.Value != null && (DateTime)e.Value < DateTime.Now);
                                memExpired.ForEach(u =>
                                {
                                    memoryData.Remove(u.Key);
                                    memoryExpiration.Remove(u.Key);
                                    usageStat.Remove(u.Key);
                                });
                            }
                            else
                            {
                                if (expiredFiles.Count == 0)
                                {
                                    Directory.GetFiles(dataPath, "*." + ExpirationFileExtension).ForEach(f =>
                                        {
                                            var buffer = File.ReadAllText(f);
                                            var expirationDate = Convert.ToDateTime(buffer);
                                            expiredFiles[Path.GetFileNameWithoutExtension(f)] = new KeyValuePair<DateTime, string>(expirationDate, f);
                                        });
                                }
                                //find out expired items
                                var fileExpired = expiredFiles.Where(e => e.Value.Key < DateTime.Now);
                                fileExpired.ForEach(u =>
                                {
                                    var dataFile = Path.ChangeExtension(u.Value.Value, DataFileExtension);
                                    File.Delete(dataFile);
                                    File.Delete(u.Value.Value);
                                    usageStat.Remove(u.Key);
                                    recycledFileCount++;
                                });
                            }
    
                            //find out least used items
                            var leastUsed = usageStat.OrderByDescending(s => s.Value.Value).Skip(maxCount - threshold);
                            leastUsed.ForEach(u =>
                                {
                                    if (isMemory)
                                    {
                                        memoryData.Remove(u.Key);
                                        memoryExpiration.Remove(u.Key);
                                    }
                                    else
                                    {
                                        var dataFile = Path.ChangeExtension(u.Value.Key, DataFileExtension);
                                        if (File.Exists(dataFile))
                                        {
                                            recycledFileCount++;
                                            File.Delete(dataFile);
                                        }
                                        if (File.Exists(u.Value.Key))
                                            File.Delete(u.Value.Key);
                                    }
                                    usageStat.Remove(u.Key);
                                });
    
                            if (!isMemory)
                            {
                                var statFilePath = dataPath + statFile;
                                var count = 0;
                                if (File.Exists(statFilePath))
                                {
                                    var buffer = File.ReadAllText(statFilePath);
                                    count = Convert.ToInt32(buffer);
                                }
                                count = count - recycledFileCount;
                                if (count < 0)
                                    count = 0;
                                File.WriteAllText(statFilePath, count.ToString());
                            }
                        }
                        break;
                    default:
                        break;
                }
            }
        }
    }
    

      

    Extensions.cs

    扩展函数

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.IO;
    
    namespace Com.SuperCache.Engine
    {
        public static class Extensions
        {
            public static void ForEach<T>(this IEnumerable<T> source, Action<T> action)
            {
                if (source != null)
                {
                    foreach (var item in source)
                    {
                        action(item);
                    }
                }
            }
    
            public static string NormalizeFileName(this string FileName)
            {
                var result = FileName;
                Path.GetInvalidFileNameChars().ForEach(c =>
                    {
                        result = result.Replace(c.ToString(), string.Empty);
                    });
                return result;
            }
        }
    }
    

      

    新建

    构造CacheEngine需要传递缓存保存到哪个文件夹。

    基于内存

    如果你不喜欢基于磁盘的缓存,可以使用基于内存,构造函数传递空字符串便可。

    增加/更新

    同一个方法:Add。用户可以指定类型(Category),譬如User,Employee等。键(Key)支持泛型,值(Data)是object。有一个overload是过期日期(ExpirationDate),默认当前时间30分钟后

    获取

    Get方法需要指定类型(Category)和键(Key)。

     

    例子

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading;
    using System.Threading.Tasks;
    using System.Diagnostics;
    using Com.SuperCache.Engine;
    
    namespace Com.SuperCache.Test
    {
        public class Foo
        {
            public string Name { get; set; }
            public int Age { get; set; }
            public double? Some { get; set; }
            public DateTime? Birthday { get; set; }
        }
    
        class Program
        {
            static void Main(string[] args)
            {
                //TestAddGet();
    
                //Thread.Sleep(4000);
                //TestExpiration();
    
                TestDefaultDiskPerformance();
                TestDefaultMemoryPerformance();
                TestRawDiskPerformance();
                TestRawMemoryPerformance();
    
                //TestConcurrent();
    
                Console.Read();
            }
    
            private static void TestConcurrent()
            {
                var w = new Stopwatch();
                w.Start();
                Parallel.For(1, 3, (a) =>
                    {
                        var employees = Enumerable.Range((a - 1) * 1000, a * 1000).Select(i => new KeyValuePair<int, string>(i, "Wilson " + i + " Chen"));
                        var engine = new CacheEngine(@"....data");
                        engine.Add<int, string>("Employee", employees, DateTime.Now.AddMinutes(1));
                    });
                w.Stop();
                Console.WriteLine("add:" + w.Elapsed);
    
                var engine2 = new CacheEngine(@"....data");
                var o = engine2.Get<int, string>("Employee", 1005);
                Console.WriteLine(o);
            }
    
            private static void TestDefaultDiskPerformance()
            {
                TestPerformance(CacheProviders.Default, @"....data");
            }
    
            private static void TestDefaultMemoryPerformance()
            {
                TestPerformance(CacheProviders.Default, string.Empty);
            }
    
            private static void TestRawDiskPerformance()
            {
                TestPerformance(CacheProviders.Raw, @"....data");
            }
    
            private static void TestRawMemoryPerformance()
            {
                TestPerformance(CacheProviders.Raw, string.Empty);
            }
    
            private static void TestPerformance(CacheProviders Provider, string DataPath)
            {
                Console.WriteLine("Performance Test: " + Provider.ToString() + ", " + (string.IsNullOrEmpty(DataPath) ? "Memory" : DataPath));
                var engine = new CacheEngine(Provider, DataPath, RecycleAlgorithms.MRU, 900, 100, RecycleModes.Passive);
                var w = new Stopwatch();
    
                w.Start();
                var employees = Enumerable.Range(0, 1000).Select(i => new KeyValuePair<int, string>(i, "Wilson " + i + " Chen"));
                engine.Add<int, string>("Employee", employees, DateTime.Now.AddMinutes(1));
                w.Stop();
                Console.WriteLine("add:" + w.Elapsed);
    
                /*w.Restart();
                employees.ForEach(key =>
                    {
                        var o1 = engine.Get<int, string>("Employee", key.Key);
                    });
                w.Stop();
                Console.WriteLine("individual get:" + w.Elapsed);*/
    
                w.Restart();
                var keys = employees.Select(i => i.Key);
                var o = engine.Get<int, string>("Employee", keys);
                w.Stop();
                Console.WriteLine("get:" + w.Elapsed);
                Console.WriteLine();
            }
    
            private static void TestExpiration()
            {
                var engine = new CacheEngine(@"....data");
                var o = engine.Get<string, Foo>("User", "wchen");
                Console.WriteLine(o != null ? o.Name : "wchen does not exist or expired");
            }
    
            private static void TestAddGet()
            {
                var engine = new CacheEngine(@"....data");
                var f = new Foo { Name = "Wilson Chen", Age = 30, Birthday = DateTime.Now, Some = 123.456 };
                engine.Add("User", "wchen", f, DateTime.Now.AddSeconds(5));
    
                var o = engine.Get<string, Foo>("User", "wchen");
                Console.WriteLine(o.Name);
    
                var o4 = engine.Get<string, Foo>("User", "foo");
                Console.WriteLine(o4 != null ? o4.Name : "foo does not exist");
    
                var o3 = engine.Get<string, string>("PlainText", "A");
                Console.WriteLine(o3 ?? "A does not exist");
            }
        }
    }
    

      

      

    性能

    通过上述性能测试例子,你会发现STSdb的磁盘存取速度要比一个记录对应一个物理文件快。想了解更多,请访问官方网站

    测试条件:1000条记录,7200RPM磁盘,i7。

    引擎 介质 写入 读取
    STSdb 磁盘 0.4s 0.07s
      内存 0.06s 0.02s
    Raw 磁盘 1.0s 0.56s
      内存  0.01s 0.002s

       

    说明

    项目中引用了System.Management是因为STSdb支持内存数据库,需要判断最大物理内存。如果不喜欢,大家可以移除引用,并且去掉STSdb4.Database.STSdb.FromMemory方法便可。

    下载

    点击这里下载

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  • 原文地址:https://www.cnblogs.com/unruledboy/p/SuperCache2.html
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