MySQL 8.0.32
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gcs_message_stage_lz4.h
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21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
22
23#ifndef GCS_MESSAGE_STAGE_LZ4_H
24#define GCS_MESSAGE_STAGE_LZ4_H
25
26#include <lz4.h>
27#include <utility>
28#include <vector>
29
32
33/**
34 This class implements LZ4 compression. It is a stateless
35 service class, thence it is thread safe.
36 */
38 public:
39 /*
40 Methods inherited from the Gcs_message_stage class.
41 */
43 uint64_t const &original_payload_size) const override;
44
45 std::unique_ptr<Gcs_stage_metadata> get_stage_header() override;
46
47 protected:
48 std::pair<bool, std::vector<Gcs_packet>> apply_transformation(
49 Gcs_packet &&packet) override;
50
51 std::pair<Gcs_pipeline_incoming_result, Gcs_packet> revert_transformation(
52 Gcs_packet &&packet) override;
53
55 const Gcs_packet &packet) const override;
56
57 public:
58 /**
59 The default threshold value in bytes.
60 */
61 static constexpr unsigned long long DEFAULT_THRESHOLD = 1024;
62
63 /**
64 Creates an instance of the stage with the default threshold in bytes set.
65 */
67
68 /**
69 Creates an instance of the stage with the given threshold in bytes.
70
71 @param enabled enables this message stage
72 @param compress_threshold messages with the payload larger
73 than compress_threshold in bytes are compressed.
74 */
76 unsigned long long compress_threshold)
77 : Gcs_message_stage(enabled), m_threshold(compress_threshold) {}
78
79 ~Gcs_message_stage_lz4() override = default;
80
81 /*
82 Return the stage code.
83 */
84 Stage_code get_stage_code() const override { return Stage_code::ST_LZ4_V1; }
85
86 /**
87 Sets the threshold in bytes after which compression kicks in.
88
89 @param threshold if the payload exceeds these many bytes, then
90 the message is compressed.
91 */
92 void set_threshold(unsigned long long threshold) { m_threshold = threshold; }
93
94 /**
95 Return the maximum payload size in bytes that can be compressed.
96 */
97 static constexpr unsigned long long max_input_compression() noexcept {
98 /*
99 The code expects that the following assumption will always hold.
100 */
101 static_assert(
102 LZ4_MAX_INPUT_SIZE <= std::numeric_limits<int>::max(),
103 "Maximum input size for lz compression exceeds the expected value");
104 return LZ4_MAX_INPUT_SIZE;
105 }
106
107 private:
108 /**
109 This marks the threshold in bytes above which a message gets compressed.
110 Messages that are smaller than this threshold are not compressed.
111 */
112 unsigned long long m_threshold;
113};
114
116 public:
117 /**
118 Creates an instance of the stage with the default threshold in bytes.
119 */
121
122 /**
123 Creates an instance of the stage with the given threshold in bytes.
124
125 @param enabled enables this message stage
126 @param compress_threshold messages with the payload larger
127 than compress_threshold in bytes are compressed.
128 */
130 unsigned long long compress_threshold)
131 : Gcs_message_stage_lz4(enabled, compress_threshold) {}
132
133 ~Gcs_message_stage_lz4_v2() override = default;
134
135 /*
136 Return the stage code.
137 */
139};
140
142 public:
143 /**
144 Creates an instance of the stage with the default threshold in bytes.
145 */
147
148 /**
149 Creates an instance of the stage with the given threshold in bytes.
150
151 @param enabled enables this message stage
152 @param compress_threshold messages with the payload larger
153 than compress_threshold in bytes are compressed.
154 */
156 unsigned long long compress_threshold)
157 : Gcs_message_stage_lz4(enabled, compress_threshold) {}
158
160
161 /*
162 Return the stage code.
163 */
165};
166
167#endif /* GCS_MESSAGE_STAGE_LZ4_H */
Definition: gcs_message_stage_lz4.h:115
Gcs_message_stage_lz4_v2()
Creates an instance of the stage with the default threshold in bytes.
Definition: gcs_message_stage_lz4.h:120
Gcs_message_stage_lz4_v2(bool enabled, unsigned long long compress_threshold)
Creates an instance of the stage with the given threshold in bytes.
Definition: gcs_message_stage_lz4.h:129
Stage_code get_stage_code() const override
Return the unique stage code.
Definition: gcs_message_stage_lz4.h:138
~Gcs_message_stage_lz4_v2() override=default
Definition: gcs_message_stage_lz4.h:141
~Gcs_message_stage_lz4_v3() override
Definition: gcs_message_stage_lz4.h:159
Gcs_message_stage_lz4_v3()
Creates an instance of the stage with the default threshold in bytes.
Definition: gcs_message_stage_lz4.h:146
Gcs_message_stage_lz4_v3(bool enabled, unsigned long long compress_threshold)
Creates an instance of the stage with the given threshold in bytes.
Definition: gcs_message_stage_lz4.h:155
Stage_code get_stage_code() const override
Return the unique stage code.
Definition: gcs_message_stage_lz4.h:164
This class implements LZ4 compression.
Definition: gcs_message_stage_lz4.h:37
std::pair< bool, std::vector< Gcs_packet > > apply_transformation(Gcs_packet &&packet) override
Implements the logic of this stage's transformation to the packet, and returns a set of one,...
Definition: gcs_message_stage_lz4.cc:67
void set_threshold(unsigned long long threshold)
Sets the threshold in bytes after which compression kicks in.
Definition: gcs_message_stage_lz4.h:92
static constexpr unsigned long long DEFAULT_THRESHOLD
The default threshold value in bytes.
Definition: gcs_message_stage_lz4.h:61
Gcs_message_stage_lz4(bool enabled, unsigned long long compress_threshold)
Creates an instance of the stage with the given threshold in bytes.
Definition: gcs_message_stage_lz4.h:75
static constexpr unsigned long long max_input_compression() noexcept
Return the maximum payload size in bytes that can be compressed.
Definition: gcs_message_stage_lz4.h:97
Gcs_message_stage::stage_status skip_apply(uint64_t const &original_payload_size) const override
Check if the apply operation which affects outgoing packets should be executed (i....
Definition: gcs_message_stage_lz4.cc:35
~Gcs_message_stage_lz4() override=default
unsigned long long m_threshold
This marks the threshold in bytes above which a message gets compressed.
Definition: gcs_message_stage_lz4.h:112
Gcs_message_stage_lz4()
Creates an instance of the stage with the default threshold in bytes set.
Definition: gcs_message_stage_lz4.h:66
std::pair< Gcs_pipeline_incoming_result, Gcs_packet > revert_transformation(Gcs_packet &&packet) override
Implements the logic to revert this stage's transformation to the packet, and returns one,...
Definition: gcs_message_stage_lz4.cc:112
std::unique_ptr< Gcs_stage_metadata > get_stage_header() override
Definition: gcs_message_stage_lz4.cc:62
Gcs_message_stage::stage_status skip_revert(const Gcs_packet &packet) const override
Check if the revert operation which affects incoming packets should be executed (i....
Definition: gcs_message_stage_lz4.cc:166
Stage_code get_stage_code() const override
Return the unique stage code.
Definition: gcs_message_stage_lz4.h:84
This is a stage in the pipeline that processes messages when they are put through the send and receiv...
Definition: gcs_message_stages.h:81
stage_status
Definition: gcs_message_stages.h:83
This class is an abstraction for the packet concept.
Definition: gcs_internal_message.h:57
Stage_code
The different stages that are currently available.
Definition: gcs_internal_message_headers.h:72
required bool enabled
Definition: replication_group_member_actions.proto:32