Choosing binary or ASCII

You can configure Content Gateway to create event log files in either of the following:

ASCII: these files can be processed using standard, off-the-shelf log-analysis tools. However, Content Gateway must perform additional processing to create the files in ASCII, resulting in an increase in overhead. Also, ASCII files tend to be larger than the equivalent binary files. ASCII log files have a .log filename extension by default.

Binary: these files generate lower system overhead, as well as generally occupying less space on the disk, depending on the type of information being logged. You must, however, use a converter application before you can read or analyze these files using standard tools. Binary log files use a .blog filename extension by default.

While binary log files typically require less disk space, this is not always the case. For example, the value 0 (zero) requires only one byte to store in ASCII but requires four bytes when stored as a binary integer. If you define a custom format that logs IP addresses, a binary log file would require only four bytes of storage per 32-bit address. However, the same IP address stored in dot notation would require around 15 characters (bytes) in an ASCII log file.

For standard log formats, you select Binary or ASCII on the Configure > Subsystems > Logging > Formats tab in the Content Gateway manager. See Setting standard log file format options. For the custom log format, you specify ASCII or Binary mode in the LogObject. Refer to Custom format.


	Note For custom log files, in addition to the ASCII and Binary options, you can also write log entries to a UNIX named pipe (a buffer in memory). Other processes can then read the data using standard I/O functions. The advantage of using this option is that Content Gateway does not have to write to disk, freeing disk space and bandwidth for other tasks. In addition, writing to a pipe does not stop when logging space is exhausted because the pipe does not use disk space. See logs_xml.config, for more information about the ASCII_PIPE option.

Before selecting ASCII versus binary for your log files, consider the type of data that will be logged. Try logging for one day using ASCII and then one day using binary. Assuming that the number of requests is roughly the same for both days, you can calculate a rough metric comparing the two formats.