Merge branch 'branch-0.5.0' into refactor_knowhere

- MS-568 - Fix gpuresource free error

- MS-572 - Milvus crash when get SIGINT

- MS-577 - Unittest Query randomly hung

- MS-587 - Count get wrong result after adding vectors and index built immediately

## Improvement

- MS-552 - Add and change the easylogging library

*src/core/thirdparty*

*src/grpc*

*easylogging++*

*SqliteMetaImpl.cpp

 No newline at end of file

# All the following configurations are default values.

server_config:

  address: 0.0.0.0                  # milvus server ip address (IPv4)

  port: 19530                       # port range: 1025 ~ 65534

  mode: single                  # deployment type: single, cluster, read_only

  deploy_mode: single               # deployment type: single, cluster_readonly, cluster_writable

  time_zone: UTC+8

db_config:

  path: @MILVUS_DB_PATH@        # milvus database path

  slave_path:                   # secondary database path, split by semicolon

  primary_path: @MILVUS_DB_PATH@    # path used to store data and meta

  secondary_path:                   # path used to store data only, split by semicolon

  # URI format: dialect://username:password@host:port/database

  # All parts except dialect are optional, but you MUST include the delimiters

  # Currently dialect supports mysql or sqlite

  backend_url: sqlite://:@:/

  backend_url: sqlite://:@:/        # URI format: dialect://username:password@host:port/database

                                    # Keep 'dialect://:@:/', and replace other texts with real values.

                                    # Replace 'dialect' with 'mysql' or 'sqlite'

  archive_disk_threshold: 0     # GB, file will be archived when disk usage exceed, 0 for no limit

  archive_days_threshold: 0     # DAYS, older files will be archived, 0 for no limit

  buffer_size: 4                # GB, maximum insert buffer size allowed

  insert_buffer_size: 4             # GB, maximum insert buffer size allowed

  build_index_gpu: 0                # gpu id used for building index

metric_config:

  auto_bootup: off              # whether enable monitoring when bootup

  enable_monitor: false             # enable monitoring or not

  collector: prometheus             # prometheus

  prometheus_config:

    port: 8080                      # port prometheus used to fetch metrics

cache_config:

  cpu_mem_capacity: 16          # GB, CPU memory size used for cache

  cpu_mem_threshold: 0.85       # percent of data kept when cache cleanup triggered

  cache_insert_data: false      # whether load data into cache when insert

  cpu_mem_capacity: 16              # GB, CPU memory used for cache

  cpu_mem_threshold: 0.85           # percentage of data kept when cache cleanup triggered

  cache_insert_data: false          # whether load inserted data into cache

engine_config:

  blas_threshold: 20

resource_config:

  mode: simple

  pool:

  resource_pool:

    - cpu

    - gpu0

    "src/core/cmake_build*" \

    "src/core/thirdparty*" \

    "src/grpc*"\

    "src/metrics/MetricBase.h"\

    "src/server/Server.cpp"\

    "src/server/DBWrapper.cpp"\

    "src/server/grpc_impl/GrpcMilvusServer.cpp"\

    Cache(int64_t capacity_gb, uint64_t cache_max_count);

    ~Cache() = default;

    int64_t usage() const { return usage_; }

    int64_t capacity() const { return capacity_; } //unit: BYTE

    int64_t usage() const {

        return usage_;

    }

    int64_t capacity() const {

        return capacity_;

    } //unit: BYTE

    void set_capacity(int64_t capacity); //unit: BYTE

    double freemem_percent() const { return freemem_percent_; };

    void set_freemem_percent(double percent) { freemem_percent_ = percent; }

    double freemem_percent() const {

        return freemem_percent_;

    }

    void set_freemem_percent(double percent) {

        freemem_percent_ = percent;

    }

    size_t size() const;

    bool exists(const std::string &key);

    mutable std::mutex mutex_;

};

}   // cache

}   // milvus

}   // zilliz

} // namespace cache

} // namespace milvus

} // namespace zilliz

#include "cache/Cache.inl"