Published: June 4th, 2025
Updated: July 3rd, 2025
Install the necessary Portage utilities and GNU Parallel:
emerge -av app-portage/portage-utils app-portage/gentoolkit sys-process/parallel
Show which packages pull in the greatest number of dependencies:
qlist -CI | sort -u | parallel 'echo $(qdepends -CqqQ {} | wc -l) {}' | sort -n > pkgs_with_most_deps.txt
What each part does:
qlist -CI: lists all installed packages without color output in
category/package format.sort -u: sorts output and removes duplicate entries.parallel: executes dependency counting through GNU Parallel for better performance.qdepends -CqqQ {}: queries dependencies without color output, quietly.wc -l: counts the dependency lines.sort -n: sorts numerically by dependency count.The output shows dependency count followed by package name, from packages with the least dependencies to greatest.
Find which packages consume the most storage:
qlist -CI | sort -u | parallel qsize -C | awk '{print $NF,$1}' | cut -d ':' -f 1 | sort -h > biggest_pkgs.txt
Breaking this down:
qsize -C: reports package sizes in human-readable format without color output.awk '{print $NF,$1}': reorders output to put size first, then package name.cut -d ':' -f 1: removes trailing colon.sort -h: sorts by human-readable numbers (handles K, M, G suffixes).This arranges packages from smallest to largest.
Merge dependency and size data in one file for analysis:
join -j 2 -o 1.1,2.1,0 <(sort -k2 pkgs_with_most_deps.txt) <(sort -k2 biggest_pkgs.txt) | sort -n | tr ' ' '\t' > combined.txt
The join command joins lines of two files on a common field:
-j 2: join on field 2 (package names).-o 1.1,2.1,0: output format (dependencies, size, package name).<(sort -k2 ...): process substitution with secondary key sorting.tr ' ' '\t': converts spaces to tabs for cleaner formatting.Print packages not yet customized in /etc/portage/package.env:
comm -13 <(awk 'match($1, /^[a-zA-Z0-9_+-]+\/[a-zA-Z0-9_+-]+$/) {print $1}' /etc/portage/package.env/* | sort -u) <(qlist -CI | sort -u)
This comm usage compares sorted lists:
-13: shows only lines unique to installation.awk 'match($1, /^[a-zA-Z0-9_+-]+\/[a-zA-Z0-9_+-]+$/)': extracts package
in category/package format.Focus on packages large enough to warrant optimization attention:
comm -13 <(awk 'match($1, /^[a-zA-Z0-9_+-]+\/[a-zA-Z0-9_+-]+$/) {print $1}' /etc/portage/package.env/* | sort -u) <(qlist -CI | sort -u) | grep -f - combined.txt | awk 'match($2, /^([0-9]{4}\.[0-9]K)|([0-9]+\.[0-9][MG])$/)' | sort -n
This adds size filtering:
grep -f -: uses the uncustomized package list as search patterns.awk 'match($2, /^([0-9]{4}\.[0-9]K)|([0-9]+\.[0-9][MG])$/)': matches
packages >=1000K.Find packages not yet customized in /etc/portage/package.env that
already need an upgrade:
comm -13 <(awk 'match($1, /^[a-zA-Z0-9_+-]+\/[a-zA-Z0-9_+-]+$/) {print $1}' /etc/portage/package.env/* | sort -u) <(EIX_LIMIT=0 eix -u -# | sort -u)
EIX_LIMIT=0: removes eix output limits.eix -u -#: lists upgradeable packages in category/package format.Use multiple sort keys for different analysis priorities:
sort -k1,1n -k2,2h combined.txt
sort -k2,2h -k1,1n combined.txt
The first command prioritizes dependency count, using size as a
tiebreaker. The second makes size the primary criterion. The h and n
refer to human-readable and numeric sorting.
These commands identify large packages that can be replaced with lightweight alternatives, which proves useful for several reasons:
I used these commands to guide CFLAGS tweaking to better optimize Gentoo in a Virtual Machine (VM), since VMs have limited resources. I use a setup where video playback doesn’t benefit from hardware acceleration at the time of writing (Qubes OS). I wanted to see if this approach could make a difference.
I think I managed to gain a few Frames Per Second (FPS) from this, but I didn’t benchmark it beyond comparing frame timings in mpv. The gain was relatively minor (<=10fps).
These days I believe strongly in benchmarking and profiling, as they make a real difference. The gains from those techniques typically exceed the gains from CFLAGS tweaking.