merges is a simple command-line tool merging multiple sorted files with small memory footprint. It is similar to mergelog which merges and sorts http log files from web servers behind round-robin DNS. The difference is that merges is not restricted to http log file format.

Usage:

> merges [-h] [-c COL] [-n] [--sep SEP] files [files ...]
-h, --help         show help message and exit
-c COL, --col COL  column index (starts from 0)
--sep SEP          column separator
-n, --numeric      numeric sort

Merge two log files, assuming fourth columns contains the timestamp and the files are space-separated:

merges -c 3 --sep ' ' a.log b.log > merged.log

Using tools like s3cmd and parallel together with merges, you can incrementally merge and sort multiple log files on Amazon S3 simultaneously while downloading is in progress:

...Add example here...

Installing merges is easy:

pip install merges

or download the source and run:

python setup.py install