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
|
// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "components/persistent_cache/persistent_cache.h"
#include <memory>
#include <optional>
#include <string>
#include <utility>
#include "base/check.h"
#include "base/check_op.h"
#include "base/metrics/histogram_functions.h"
#include "base/notreached.h"
#include "base/strings/strcat.h"
#include "base/synchronization/lock.h"
#include "base/timer/elapsed_timer.h"
#include "base/types/expected.h"
#include "components/persistent_cache/backend.h"
#include "components/persistent_cache/backend_type.h"
#include "components/persistent_cache/pending_backend.h"
#include "components/persistent_cache/sqlite/sqlite_backend_impl.h"
#include "components/persistent_cache/transaction_error.h"
namespace persistent_cache {
const char* GetBackendTypeName(BackendType backend_type) {
switch (backend_type) {
case BackendType::kSqlite:
return "SQLite";
}
}
// static
std::unique_ptr<PersistentCache> PersistentCache::Bind(
PendingBackend pending_backend) {
// If there is ever occasion to have more than one type, branch on the type
// here.
if (auto backend = SqliteBackendImpl::Bind(std::move(pending_backend));
backend) {
return std::make_unique<PersistentCache>(std::move(backend));
}
return nullptr;
}
PersistentCache::PersistentCache(std::unique_ptr<Backend> backend)
: backend_(std::move(backend)) {
CHECK(backend_);
}
PersistentCache::~PersistentCache() = default;
base::expected<std::optional<EntryMetadata>, TransactionError>
PersistentCache::Find(std::string_view key, BufferProvider buffer_provider) {
std::optional<base::ElapsedTimer> timer = MaybeGetTimerForHistogram();
auto entry_metadata = backend_->Find(key, buffer_provider);
if (timer.has_value()) {
base::UmaHistogramMicrosecondsTimes(GetFullHistogramName("Find"),
timer->Elapsed());
}
return entry_metadata;
}
base::expected<void, TransactionError> PersistentCache::Insert(
std::string_view key,
base::span<const uint8_t> content,
EntryMetadata metadata) {
std::optional<base::ElapsedTimer> timer = MaybeGetTimerForHistogram();
auto result = backend_->Insert(key, content, metadata);
if (timer.has_value()) {
base::UmaHistogramMicrosecondsTimes(GetFullHistogramName("Insert"),
timer->Elapsed());
}
return result;
}
LockState PersistentCache::Abandon() {
return backend_->Abandon();
}
Backend* PersistentCache::GetBackendForTesting() {
return backend_.get();
}
std::optional<base::ElapsedTimer> PersistentCache::MaybeGetTimerForHistogram() {
std::optional<base::ElapsedTimer> timer;
base::AutoLock lock(metrics_subsampler_lock_);
if (metrics_subsampler_.ShouldSample(kTimingLoggingProbability)) {
timer.emplace();
}
return timer;
}
std::string PersistentCache::GetFullHistogramName(std::string_view name) const {
const char* file_access_suffix =
backend_->IsReadOnly() ? ".ReadOnly" : ".ReadWrite";
return base::StrCat({"PersistentCache.", name, ".",
GetBackendTypeName(backend_->GetType()),
file_access_suffix});
}
} // namespace persistent_cache
|
