MTAppenderFile

A simplified high-performance log component for *OS base on Tencent Mars xlog, is used in MTHawkeye for performance record data persistance.

Usage

Creata a AppenderFile by using Objective-C API,

MTAppenderFile *file = [[MTAppenderFile alloc] initWithFileDir:dirName name:fileName];
[file open];

Then use appendText: or appendUTF8Text: to append line data.

[file appendText:@"test line"];
[file appendUTF8Text:"test line"];

Details

Each AppenderFile contains two files with the same file name, and different extensions. The first one is mmap file for high speed cache with the extension .mmap2, it's size is 150KB. The other file a extension .mtlog, log data transfered to this file when the mmap file needs to be dumped.

For example, if you create an AppenderFile whose name is records, the actual files are: records.mmap2 and records.mtlog. You need to merge the two files when reading, which is the complete records.

Attention for reading stored data:

• Both files need to be read, first *.mmap2, then *.mtlog, and then put the content together.
• When reading the *.mmap2 file, only non-dirty data is needed. when the \0\0\0 line is encountered, the complete content of mmap has been read, and the content after that is dirty data, which should be ignored.

Contributing

For more information about contributing issues or pull requests, see Contributing Guide。

Base On

1. Tencent-Mars
2. 微信终端跨平台组件 mars 系列（一） - 高性能日志模块xlog