Must I sort the .bam or .sam file before do the feature count?

Question

[Xiaokang]

I saw some people sort the .bam or .sam file got from alignment, before the next step which is feature count. But what's the point of doing that? To speed up the subsequent process?

Answer 1

[GenoMax]

Not necessary but since one needs sorted files for other things I find it convenient to sort upfront.

Automatically sort paired-end reads. Users can provide either location-sorted or name- sorted bams files to featureCounts. Read sorting is implemented on the fly and it only incurs minimal time cost