aboutsummaryrefslogtreecommitdiff
path: root/zenserver/cache/structuredcachestore.h
blob: 2cc3abb53ad35dbc8d6501ffe0b2cb9d2efb68f8 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include <zencore/compactbinary.h>
#include <zencore/iobuffer.h>
#include <zencore/iohash.h>
#include <zencore/thread.h>
#include <zencore/uid.h>
#include <zenstore/cas.h>

#pragma warning(push)
#pragma warning(disable : 4127)
#include <tsl/robin_map.h>
#pragma warning(pop)

#include <compare>
#include <filesystem>
#include <unordered_map>

namespace zen {

class WideStringBuilderBase;
class CasStore;

/******************************************************************************

  /$$$$$$$$                        /$$$$$$                   /$$
 |_____ $$                        /$$__  $$                 | $$
	  /$$/  /$$$$$$ /$$$$$$$     | $$  \__/ /$$$$$$  /$$$$$$| $$$$$$$  /$$$$$$
	 /$$/  /$$__  $| $$__  $$    | $$      |____  $$/$$_____| $$__  $$/$$__  $$
	/$$/  | $$$$$$$| $$  \ $$    | $$       /$$$$$$| $$     | $$  \ $| $$$$$$$$
   /$$/   | $$_____| $$  | $$    | $$    $$/$$__  $| $$     | $$  | $| $$_____/
  /$$$$$$$|  $$$$$$| $$  | $$    |  $$$$$$|  $$$$$$|  $$$$$$| $$  | $|  $$$$$$$
 |________/\_______|__/  |__/     \______/ \_______/\_______|__/  |__/\_______/

  Cache store for UE5. Restricts keys to "{bucket}/{hash}" pairs where the hash
  is 40 (hex) chars in size. Values may be opaque blobs or structured objects
  which can in turn contain references to other objects (or blobs).

******************************************************************************/

struct ZenCacheValue
{
	IoBuffer Value;
	CbObject IndexData;
};

class ZenCacheMemoryLayer
{
public:
	ZenCacheMemoryLayer();
	~ZenCacheMemoryLayer();

	bool Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
	void Put(std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
	bool DropBucket(std::string_view Bucket);
	void Scrub(ScrubContext& Ctx);

private:
	struct CacheBucket
	{
		RwLock							 m_bucketLock;
		tsl::robin_map<IoHash, IoBuffer> m_cacheMap;

		bool Get(const IoHash& HashKey, ZenCacheValue& OutValue);
		void Put(const IoHash& HashKey, const ZenCacheValue& Value);
	};

	RwLock										 m_Lock;
	std::unordered_map<std::string, CacheBucket> m_Buckets;
};

class ZenCacheDiskLayer
{
public:
	ZenCacheDiskLayer(CasStore& Cas, const std::filesystem::path& RootDir);
	~ZenCacheDiskLayer();

	bool Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
	void Put(std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
	bool DropBucket(std::string_view Bucket);
	void Flush();
	void Scrub(ScrubContext& Ctx);

private:
	/** A cache bucket manages a single directory containing
		metadata and data for that bucket
	  */
	struct CacheBucket;

	CasStore&									 m_CasStore;
	std::filesystem::path						 m_RootDir;
	RwLock										 m_Lock;
	std::unordered_map<std::string, CacheBucket> m_Buckets;	 // TODO: make this case insensitive
};

class ZenCacheStore
{
public:
	ZenCacheStore(CasStore& Cas, const std::filesystem::path& RootDir);
	~ZenCacheStore();

	bool Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
	void Put(std::string_view Bucket, const IoHash& HashKey, const ZenCacheValue& Value);
	bool DropBucket(std::string_view Bucket);
	void Flush();
	void Scrub(ScrubContext& Ctx);

private:
	std::filesystem::path m_RootDir;
	ZenCacheMemoryLayer	  m_MemLayer;
	ZenCacheDiskLayer	  m_DiskLayer;
	uint64_t			  m_DiskLayerSizeThreshold = 4 * 1024;
	uint64_t			  m_LastScrubTime		   = 0;
};

/** Tracks cache entry access, stats and orchestrates cleanup activities
 */
class ZenCacheTracker
{
public:
	ZenCacheTracker(ZenCacheStore& CacheStore);
	~ZenCacheTracker();

	void TrackAccess(std::string_view Bucket, const IoHash& HashKey);
	void Flush();

private:
};

}  // namespace zen