[Mageia-dev] [ANN] [RFC] support for deltarpms in urpmi

Tue Nov 27 17:10:06 CET 2012

Hi
+
+urpmi now have basic support for delta rpms, aka it can install them
+(never worked before).
+We could think about providing updates as delta rpms for mga3.
+Example for libreoffice:
+both
+core/release/libreoffice-writer-3.5.3.2-1.mga2.x86_64.rpm and
+libreoffice-writer-3.5.5.3-0.3.mga2.x86_64.rpm
+are 4,2M big but:
+makedeltarpm core/release/libreoffice-writer-3.5.3.2-1.mga2.x86_64.rpm
+core/updates/libreoffice-writer-3.5.5.3-0.3.mga2.x86_64.rpm
+/tmp/libreoffice-writer-3.5.5.3-0.3.mga2.x86_64.drpm2
+results in a 405k delta rpm.
+Aka a 10 fold reduction in download needs.
+
+We should think about what's needed:
+- new deltarpm update media to hold deltarpms ?
+- recording source version in synthesis
+- keeping:
+  o all deltarpm (not as big as full classic rpms)
+  o or only keeping both:
+    * core/release > latest core/updates
+    * previous core/updates > latest core/updates
+- option do disable deltarpm support in /etc/urpmi.cfg?
+- having a fallback in urpmi if applydeltarpm fails
+- having urpmi select the right package
+  o either deltarpm if there's one for installed_version -> update_version path
+  o or regular update package else
+
+WDYT?
+