docs: add high-performance-reading.md (#178)

zh_CN/development-guide/high-performance-reading.md

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+# 高性能查询
+
+除数据建模以及索引外，通过优化配置也能极大的提升数据查询性能。本章节主要介绍如何通过优化配置，提升数据查询的效率。
+
+## 配置 meta 缓存
+
+数据在查询的过程中，会读取存储引擎中的 meta 信息用于查询优化，频繁的 IO 会增加查询过程中额外的开销，因此将该部份信息进行缓存能极大的提升查询效率。建议值：存储文件大小的 1%。配置如下：
+
+```toml
+[ts_engine]
+
+# Cache size for SST file metadata. Setting it to 0 to disable the cache.
+# Default: 128M
+meta_cache_size = "256M"
+```
+
+注：当内存过小，缓存被高频换入、换出，可能会导致查询变慢。
+
+## 配置热数据缓存
+
+在使用对象外存储（OBS、Azure、S3、MinIO等）时，为降低远程 IO 带来的性能损失，可以配置混合缓存（内存 + 磁盘），将热数据缓存在 内存/磁盘 中，以加速查询。具体配置如下：
+
+```toml
+
+# The configurations of storage.
+[storage]
+
+# The configurations of the file meta memory cache.
+[storage.file_meta_cache.memory]
+# 0 means disable mem file meta cache
+# Default: "512MB"
+capacity = "512MB"
+
+# The shard number of mem cache
+# More shards will help distribute the load and improve performance by reducing contention.
+# But too many shards might lead to increased overhead due to managing more individual cache segments.
+# Default: 16
+# shards = 16
+
+# !!! Disk cache configuration not working on standalone mode
+# The configurations of the file meta disk cache.
+[storage.file_meta_cache.disk]
+# Disk cache capicity
+# 0 means disable disk cache
+# Default: "0GB"
+capacity = "1GB"
+
+# The directory where the disk cache will be stored
+# Default: "/var/lib/datalayers/meta_cache"
+path = "/var/lib/datalayers/meta_cache"
+
+
+# The configurations of the file data memory cache.
+[storage.file_cache.memory]
+# 0 means disable mem cache
+# Default: "0MB"
+capacity = "1GB"
+
+
+# The configurations of the file data disk cache.
+# !!! Disk cache configuration not working on standalone mode
+[storage.file_cache.disk]
+# Disk cache capicity
+# 0 means disable disk cache
+# Default: "10GB"
+capacity = "30GB"
+
+# The directory where the disk cache will be stored
+# Default: "/var/lib/datalayers/file_cache"
+path = "/var/lib/datalayers/file_cache"
+```
+
+注：当内存、磁盘设置较小、且查询场景无热点数据，缓存的高频的换入、换出可能影响查询性能。