Mercurial > hg > orthanc
diff Core/Cache/MemoryObjectCache.cpp @ 3557:4d809b2e1141
better cache toolbox: MemoryObjectCache
author | Sebastien Jodogne <s.jodogne@gmail.com> |
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date | Mon, 04 Nov 2019 15:18:38 +0100 |
parents | |
children | 4812825e69fc |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Core/Cache/MemoryObjectCache.cpp Mon Nov 04 15:18:38 2019 +0100 @@ -0,0 +1,259 @@ +/** + * Orthanc - A Lightweight, RESTful DICOM Store + * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics + * Department, University Hospital of Liege, Belgium + * Copyright (C) 2017-2019 Osimis S.A., Belgium + * + * This program is free software: you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, either version 3 of the + * License, or (at your option) any later version. + * + * In addition, as a special exception, the copyright holders of this + * program give permission to link the code of its release with the + * OpenSSL project's "OpenSSL" library (or with modified versions of it + * that use the same license as the "OpenSSL" library), and distribute + * the linked executables. You must obey the GNU General Public License + * in all respects for all of the code used other than "OpenSSL". If you + * modify file(s) with this exception, you may extend this exception to + * your version of the file(s), but you are not obligated to do so. If + * you do not wish to do so, delete this exception statement from your + * version. If you delete this exception statement from all source files + * in the program, then also delete it here. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + **/ + + +#include "../PrecompiledHeaders.h" +#include "MemoryObjectCache.h" + +namespace Orthanc +{ + class MemoryObjectCache::Item : public boost::noncopyable + { + private: + ICacheable* value_; + boost::posix_time::ptime time_; + + public: + explicit Item(ICacheable* value) : // Takes ownership + value_(value), + time_(boost::posix_time::second_clock::local_time()) + { + if (value == NULL) + { + throw OrthancException(ErrorCode_NullPointer); + } + } + + ~Item() + { + assert(value_ != NULL); + delete value_; + } + + ICacheable& GetValue() const + { + assert(value_ != NULL); + return *value_; + } + + const boost::posix_time::ptime& GetTime() const + { + return time_; + } + }; + + + void MemoryObjectCache::Recycle(size_t targetSize) + { + // WARNING: "cacheMutex_" must be locked + while (currentSize_ > targetSize) + { + assert(!content_.IsEmpty()); + + Item* item = NULL; + content_.RemoveOldest(item); + + assert(item != NULL); + const size_t size = item->GetValue().GetMemoryUsage(); + delete item; + + assert(currentSize_ >= size); + currentSize_ -= size; + } + + // Post-condition: "currentSize_ <= targetSize" + } + + + MemoryObjectCache::MemoryObjectCache() : + currentSize_(0), + maxSize_(100 * 1024 * 1024) // 100 MB + { + } + + + MemoryObjectCache::~MemoryObjectCache() + { + Recycle(0); + assert(content_.IsEmpty()); + } + + + size_t MemoryObjectCache::GetMaximumSize() + { +#if !defined(__EMSCRIPTEN__) + boost::mutex::scoped_lock lock(cacheMutex_); +#endif + + return maxSize_; + } + + + void MemoryObjectCache::SetMaximumSize(size_t size) + { + if (size == 0) + { + throw OrthancException(ErrorCode_ParameterOutOfRange); + } + +#if !defined(__EMSCRIPTEN__) + // Make sure no accessor is currently open (as its data may be + // removed if recycling is needed) + WriterLock contentLock(contentMutex_); + + // Lock the global structure of the cache + boost::mutex::scoped_lock cacheLock(cacheMutex_); +#endif + + Recycle(size); + maxSize_ = size; + } + + + void MemoryObjectCache::Acquire(const std::string& key, + ICacheable* value) + { + std::auto_ptr<Item> item(new Item(value)); + + if (value == NULL) + { + throw OrthancException(ErrorCode_NullPointer); + } + else + { +#if !defined(__EMSCRIPTEN__) + // Make sure no accessor is currently open (as its data may be + // removed if recycling is needed) + WriterLock contentLock(contentMutex_); + + // Lock the global structure of the cache + boost::mutex::scoped_lock cacheLock(cacheMutex_); +#endif + + const size_t size = item->GetValue().GetMemoryUsage(); + + if (size > maxSize_) + { + // This object is too large to be stored in the cache, discard it + } + else if (content_.Contains(key)) + { + // Value already stored, don't overwrite the old value + content_.MakeMostRecent(key); + } + else + { + Recycle(maxSize_ - size); // Post-condition: currentSize_ <= maxSize_ - size + assert(currentSize_ + size <= maxSize_); + + content_.Add(key, item.release()); + currentSize_ += size; + } + } + } + + + void MemoryObjectCache::Invalidate(const std::string& key) + { +#if !defined(__EMSCRIPTEN__) + // Make sure no accessor is currently open (as it may correspond + // to the key to remove) + WriterLock contentLock(contentMutex_); + + // Lock the global structure of the cache + boost::mutex::scoped_lock cacheLock(cacheMutex_); +#endif + + Item* item = NULL; + if (content_.Contains(key, item)) + { + assert(item != NULL); + const size_t size = item->GetValue().GetMemoryUsage(); + delete item; + + content_.Invalidate(key); + + assert(currentSize_ >= size); + currentSize_ -= size; + } + } + + + MemoryObjectCache::Reader::Reader(MemoryObjectCache& cache, + const std::string& key) : +#if !defined(__EMSCRIPTEN__) + contentLock_(cache.contentMutex_), + cacheLock_(cache.cacheMutex_), +#endif + item_(NULL) + { + if (cache.content_.Contains(key, item_)) + { + cache.content_.MakeMostRecent(key); + } + +#if !defined(__EMSCRIPTEN__) + cacheLock_.unlock(); + + if (item_ == NULL) + { + contentLock_.unlock(); + } +#endif + } + + + ICacheable& MemoryObjectCache::Reader::GetValue() const + { + if (IsValid()) + { + return item_->GetValue(); + } + else + { + throw OrthancException(ErrorCode_BadSequenceOfCalls); + } + } + + + const boost::posix_time::ptime& MemoryObjectCache::Reader::GetTime() const + { + if (IsValid()) + { + return item_->GetTime(); + } + else + { + throw OrthancException(ErrorCode_BadSequenceOfCalls); + } + } +}