group_gt1_C

This program is an intermediate step in the processing of 16S rRNA genes. It generates a fasta file given an input of RNA-sequences and identifiers. Uses a binary tree-based algorithm to lexicographically and categorize RNA strings. Sorts resulting array of pointers using quicksort by identifier count.

group_gt1_C is written to improve the performance of the workflow_e.sh pipeline.

Usage:

Replace group_gt1.pl with files from group_gt1_C. The inputs are exactly the same.

make

./group_gt1 directory_in/input_name.txt directory_out/output_name.txt

Performance:

Given a 9.1GB rekeyed_tab.txt file with 14,246,039 RNA sequences:

1. Consumes approximately 1.85GB to the 2.55GB consumed by the Perl implementation. (~25% less memory consumption)
2. This was profiled using the memory tool Valgrind on a Unix system.
3. Runs in average 1m 33s vs 3m 57s across 10 pipeline instances. (>200% performance increase)
4. This was benchmarked using the linux time function.
5. Each instance was run on a cold boot to standardize loading time of the rekeyed_tab.txt file.

System specs:

• Late 2011 Macbook Pro.
• Intel Core i7-2760QM CPU @ 2.40 GHz.
• 16 GB 1333MHz DDR3 RAM.