| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| |
| #ifndef IMPALA_UTIL_MEM_INFO_H |
| #define IMPALA_UTIL_MEM_INFO_H |
| |
| #include <string> |
| #include <boost/cstdint.hpp> |
| |
| #include "common/logging.h" |
| |
| namespace impala { |
| |
| /// Provides the amount of physical memory available. |
| /// Populated from /proc/meminfo. |
| /// TODO: Allow retrieving of cgroup memory limits, |
| /// e.g., by checking /sys/fs/cgroup/memory/groupname/impala/memory.limit_in_bytes |
| /// TODO: Combine mem-info, cpu-info and disk-info into hardware-info? |
| class MemInfo { |
| public: |
| /// Initialize MemInfo. |
| static void Init(); |
| |
| /// Get total physical memory in bytes (ignores cgroups memory limits). |
| static int64_t physical_mem() { |
| DCHECK(initialized_); |
| return physical_mem_; |
| } |
| |
| /// Returns the systems memory overcommit settings, typically the values are 0,1, and 2 |
| static int32_t vm_overcommit() { |
| DCHECK(initialized_); |
| return vm_overcommit_; |
| } |
| |
| /// Returns the systems memory commit limit. This value is only of importance if the |
| /// memory overcommit setting is set to 2. |
| static int64_t commit_limit() { |
| DCHECK(initialized_); |
| return commit_limit_; |
| } |
| |
| static std::string DebugString(); |
| |
| private: |
| |
| static void ParseOvercommit(); |
| |
| static bool initialized_; |
| static int64_t physical_mem_; |
| |
| /// See https://www.kernel.org/doc/Documentation/filesystems/proc.txt for more details on |
| /// the specific meaning of the below variables and |
| /// https://www.kernel.org/doc/Documentation/vm/overcommit-accounting for more details on |
| /// overcommit accounting. |
| |
| /// Indicating the kernel overcommit settings |
| //(e.g. heuristic based / always / strict) |
| static int32_t vm_overcommit_; |
| |
| /// If overcommit is turned off the maximum allocatable memory |
| static int64_t commit_limit_; |
| }; |
| |
| } |
| #endif |