ceph/src/rocksdb/java/rocksjni/memory_util.cc

   1 // Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
   2 //  This source code is licensed under both the GPLv2 (found in the
   3 //  COPYING file in the root directory) and Apache 2.0 License
   4 //  (found in the LICENSE.Apache file in the root directory).
   5
   6 #include <jni.h>
   7 #include <map>
   8 #include <string>
   9 #include <unordered_set>
  10 #include <vector>
  11
  12 #include "include/org_rocksdb_MemoryUtil.h"
  13
  14 #include "rocksjni/portal.h"
  15
  16 #include "rocksdb/utilities/memory_util.h"
  17
  18
  19 /*
  20  * Class:     org_rocksdb_MemoryUtil
  21  * Method:    getApproximateMemoryUsageByType
  22  * Signature: ([J[J)Ljava/util/Map;
  23  */
  24 jobject Java_org_rocksdb_MemoryUtil_getApproximateMemoryUsageByType(
  25     JNIEnv *env, jclass /*jclazz*/, jlongArray jdb_handles, jlongArray jcache_handles) {
  26
  27   std::vector<rocksdb::DB*> dbs;
  28   jsize db_handle_count = env->GetArrayLength(jdb_handles);
  29   if(db_handle_count > 0) {
  30     jlong *ptr_jdb_handles = env->GetLongArrayElements(jdb_handles, nullptr);
  31     if (ptr_jdb_handles == nullptr) {
  32       // exception thrown: OutOfMemoryError
  33       return nullptr;
  34     }
  35     for (jsize i = 0; i < db_handle_count; i++) {
  36       dbs.push_back(reinterpret_cast<rocksdb::DB *>(ptr_jdb_handles[i]));
  37     }
  38     env->ReleaseLongArrayElements(jdb_handles, ptr_jdb_handles, JNI_ABORT);
  39   }
  40
  41   std::unordered_set<const rocksdb::Cache*> cache_set;
  42   jsize cache_handle_count = env->GetArrayLength(jcache_handles);
  43   if(cache_handle_count > 0) {
  44     jlong *ptr_jcache_handles = env->GetLongArrayElements(jcache_handles, nullptr);
  45     if (ptr_jcache_handles == nullptr) {
  46       // exception thrown: OutOfMemoryError
  47       return nullptr;
  48     }
  49     for (jsize i = 0; i < cache_handle_count; i++) {
  50       auto *cache_ptr =
  51           reinterpret_cast<std::shared_ptr<rocksdb::Cache> *>(ptr_jcache_handles[i]);
  52       cache_set.insert(cache_ptr->get());
  53     }
  54     env->ReleaseLongArrayElements(jcache_handles, ptr_jcache_handles, JNI_ABORT);
  55   }
  56
  57   std::map<rocksdb::MemoryUtil::UsageType, uint64_t> usage_by_type;
  58   if(rocksdb::MemoryUtil::GetApproximateMemoryUsageByType(dbs, cache_set, &usage_by_type) != rocksdb::Status::OK()) {
  59     // Non-OK status
  60     return nullptr;
  61   }
  62
  63   jobject jusage_by_type = rocksdb::HashMapJni::construct(
  64       env, static_cast<uint32_t>(usage_by_type.size()));
  65   if (jusage_by_type == nullptr) {
  66     // exception occurred
  67     return nullptr;
  68   }
  69   const rocksdb::HashMapJni::FnMapKV<const rocksdb::MemoryUtil::UsageType, const uint64_t, jobject, jobject>
  70       fn_map_kv =
  71       [env](const std::pair<rocksdb::MemoryUtil::UsageType, uint64_t>& pair) {
  72         // Construct key
  73         const jobject jusage_type =
  74             rocksdb::ByteJni::valueOf(env, rocksdb::MemoryUsageTypeJni::toJavaMemoryUsageType(pair.first));
  75         if (jusage_type == nullptr) {
  76           // an error occurred
  77           return std::unique_ptr<std::pair<jobject, jobject>>(nullptr);
  78         }
  79         // Construct value
  80         const jobject jusage_value =
  81             rocksdb::LongJni::valueOf(env, pair.second);
  82         if (jusage_value == nullptr) {
  83           // an error occurred
  84           return std::unique_ptr<std::pair<jobject, jobject>>(nullptr);
  85         }
  86         // Construct and return pointer to pair of jobjects
  87         return std::unique_ptr<std::pair<jobject, jobject>>(
  88             new std::pair<jobject, jobject>(jusage_type,
  89                                             jusage_value));
  90       };
  91
  92   if (!rocksdb::HashMapJni::putAll(env, jusage_by_type, usage_by_type.begin(),
  93                                    usage_by_type.end(), fn_map_kv)) {
  94     // exception occcurred
  95     jusage_by_type = nullptr;
  96   }
  97
  98   return jusage_by_type;
  99
 100 }