impact of installation counts on perceived quality: a case study on debian

Impact of Installation Counts on Perceived Quality:

A Case Study on Debian

Israel Herraiz Emad ShihabThanh H.D. NguyenAhmed E. Hassan

israel.herraiz@upm.es

Intelligence throughout the lifetime of a software system

From inception to production

http://sail.cs.queensu.ca

A Unique View ofSoftware Quality in the Large

Debian has an eco-system of 16,000 packagesThousands of involved developers

~500 reported bugs per month Installation and usage are tracked

The Development Process of Debian

GCC CVS

Mozilla CVS Firefox Browser

ThunderbirdEmail

Upstream Package

GCC C Compiler

GCC CVSDebian BugDatabase

Tracking Installations

Popularity: total install countsRecent Use (Recent 30 days)

Old Use (Beyond 30 days)

Ultimate Debian Database (UDD)

Source Packages

mypkg libmypkg

mypkg

libmypkg-dev

mypkg-common

Type (Game, Dev, Editor)Priority (Essential , Optional)

Bugs (fixed, reported, forwarded)Reporter (email)

Binary Packages

Sub-linear growth (X1/constant)

Log(installations)

Log(

Bugs

)

More installations More Bugs

Log(installations)

Log(

Bugs

)

Pattern holds for optional packages

Log(installations)

Log(

Bugs

)

Essential packages

Log(installations)

Log(

Bugs

)

Pattern holds for Fixed Bugs

Log(installations)

Log(

Fixe

d Bu

gs)

Bugs increase with recent use

Recent Use

Log(

fixed

bug

s)

Bug profiles differ between package types

Technical users Casual users

Software Development Games

“With many eyes, all bugs become shallow”Eric Raymond

Bug Management OverheadVery low % of bugs are fixed for widely installed packages

Log(installations)

% o

f Fix

ed B

ugs

Sub-linear growth (X1/constant)

Log(installations)

Log(

Bugs

)

Is there a representative set of packages?

Log (installations)

Log(

Bugs

)

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