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March 11, 2015 05:33
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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,137 @@ #include <string> #include <unordered_set> #include <boost/intrusive_ptr.hpp> #include <boost/noncopyable.hpp> #include <gperftools/malloc_extension.h> #include <assert.h> #include <string.h> class Item : boost::noncopyable { public: Item(const char* key, uint32_t flags, int valuelen, uint64_t cas) : keylen_(strlen(key)), valuelen_(valuelen), cas_(cas) { char buf[64]; flaglen_ = snprintf(buf, sizeof buf, " %u %d\r\n", flags, valuelen); data_ = static_cast<char*>(::malloc(totalLen())); memcpy(data_, key, keylen_); memcpy(data_ + keylen_, buf, flaglen_); data_[totalLen() - 2] = '\r'; data_[totalLen() - 1] = '\n'; } ~Item() { ::free(data_); } void assign(const char* value, int valuelen) { assert(valuelen <= valuelen_); memcpy(data_ + keylen_ + flaglen_, value, valuelen); } size_t hash() const { return std::_Hash_impl::hash(data_, keylen_); } bool equals(const Item& rhs) const { return keylen_ == rhs.keylen_ && memcmp(data_, rhs.data_, keylen_) == 0; } int inc_ref() const { return ++refcount_; } int dec_ref() const { return --refcount_; } private: int totalLen() const { return keylen_ + flaglen_ + valuelen_ + 2; } const uint8_t keylen_; uint8_t flaglen_ = 0; mutable uint16_t refcount_ = 0; const int valuelen_; const uint64_t cas_; char* data_ = nullptr; }; typedef boost::intrusive_ptr<const Item> ConstItemPtr; void intrusive_ptr_add_ref(const Item* p) { if (p->inc_ref() == 0) assert(false && "refcount overflow"); } void intrusive_ptr_release(const Item* p) { if (p->dec_ref() == 0) delete p; } struct Hash { size_t operator()(const ConstItemPtr& x) const { return x->hash(); } }; struct Equal { bool operator()(const ConstItemPtr& x, const ConstItemPtr& y) const { return x->equals(*y); } }; typedef std::unordered_set<ConstItemPtr, Hash, Equal> Map; int main(int argc, char* argv[]) { MallocExtension::Initialize(); int items = argc > 1 ? atoi(argv[1]) : 1000 * 1000; int keylen = 10; int valuelen = 100; char key[256] = { 0 }; std::string value; Map theMap; for (int i = 0; i < items; ++i) { snprintf(key, sizeof key, "%0*d", keylen, i); value.assign(valuelen, "0123456789"[i % 10]); boost::intrusive_ptr<Item> item(new Item(key, 0, valuelen, 1)); item->assign(value.data(), value.size()); auto result = theMap.insert(std::move(item)); assert(result.second); } printf("sizeof Item = %zd\n", sizeof(Item)); printf("sizeof intrusive_ptr = %zd\n", sizeof(boost::intrusive_ptr<Item>)); printf("items = %zd\n", theMap.size()); char buf[65536] = ""; MallocExtension::instance()->GetStats(buf, sizeof buf); printf("%s\n", buf); } This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,139 @@ #include <string> #include <unordered_set> #include <boost/intrusive_ptr.hpp> #include <boost/noncopyable.hpp> #include <gperftools/malloc_extension.h> #include <assert.h> #include <string.h> class Item : boost::noncopyable { public: Item(const char* key, uint32_t flags, int valuelen, uint64_t cas) : keylen_(strlen(key)), valuelen_(valuelen), hash_(std::_Hash_impl::hash(key, keylen_)), cas_(cas) { char buf[64]; flaglen_ = snprintf(buf, sizeof buf, " %u %d\r\n", flags, valuelen); data_ = static_cast<char*>(::malloc(totalLen())); memcpy(data_, key, keylen_); memcpy(data_ + keylen_, buf, flaglen_); data_[totalLen() - 2] = '\r'; data_[totalLen() - 1] = '\n'; } ~Item() { ::free(data_); } void assign(const char* value, int valuelen) { assert(valuelen <= valuelen_); memcpy(data_ + keylen_ + flaglen_, value, valuelen); } size_t hash() const { return hash_; } bool equals(const Item& rhs) const { return keylen_ == rhs.keylen_ && memcmp(data_, rhs.data_, keylen_) == 0; } int inc_ref() const { return ++refcount_; } int dec_ref() const { return --refcount_; } private: int totalLen() const { return keylen_ + flaglen_ + valuelen_ + 2; } const uint8_t keylen_; uint8_t flaglen_ = 0; mutable uint16_t refcount_ = 0; const int valuelen_; const size_t hash_; const uint64_t cas_; char* data_ = nullptr; }; typedef boost::intrusive_ptr<const Item> ConstItemPtr; void intrusive_ptr_add_ref(const Item* p) { if (p->inc_ref() == 0) assert(false && "refcount overflow"); } void intrusive_ptr_release(const Item* p) { if (p->dec_ref() == 0) delete p; } struct Hash { size_t operator()(const ConstItemPtr& x) const noexcept // noexcept is the key { return x->hash(); } }; struct Equal { bool operator()(const ConstItemPtr& x, const ConstItemPtr& y) const { return x->equals(*y); } }; typedef std::unordered_set<ConstItemPtr, Hash, Equal> Map; int main(int argc, char* argv[]) { MallocExtension::Initialize(); int items = argc > 1 ? atoi(argv[1]) : 1000 * 1000; int keylen = 10; int valuelen = 100; char key[256] = { 0 }; std::string value; Map theMap; for (int i = 0; i < items; ++i) { snprintf(key, sizeof key, "%0*d", keylen, i); value.assign(valuelen, "0123456789"[i % 10]); boost::intrusive_ptr<Item> item(new Item(key, 0, valuelen, 1)); item->assign(value.data(), value.size()); auto result = theMap.insert(std::move(item)); assert(result.second); } printf("sizeof Item = %zd\n", sizeof(Item)); printf("sizeof intrusive_ptr = %zd\n", sizeof(boost::intrusive_ptr<Item>)); printf("items = %zd\n", theMap.size()); char buf[65536] = ""; MallocExtension::instance()->GetStats(buf, sizeof buf); printf("%s\n", buf); }