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BenLangmead / bowtie2

A fast and sensitive gapped read aligner
GNU General Public License v3.0
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Does the number of threads affect randomness? #473

Closed EReckase closed 1 month ago

EReckase commented 2 months ago

In some of our testing, we've found that while we leave --seed unset (which I assume defaults to 0), changing the number of threads used to perform the calculations sometimes provides differing results. Does the threads parameter need to be added to the documentation as a source of non-determinism?

EReckase commented 1 month ago

This appears to possibly be related to the order of the reads within the input fastqs rather than the number of threads.

EReckase commented 1 month ago

This ended up not being bowtie2 but some other post-processing.