* Alright. extract_install may become a longstanding operation so it is

not fair to disable keyboard interrupts before that. The real critical 
  path contains store_pisi_files which can lead to a situation that the 
  new package's pisi files extracted and old package's are deleted from 
  /var/lib/package but the db may not be updated. So db thinks the old 
  version is installed but pisi files are deleted without its knowledge.
  And this leads to that nasty bug.

  Anyway, this only increases the response time without effecting the real
  fix.

pisi/atomicoperations.py

@@ -106,13 +106,11 @@ class Install(AtomicOperation):
         self.ask_reinstall = ask_reinstall
         self.check_requirements()
         self.check_relations()
-
-        ctx.disable_keyboard_interrupts()
-
         self.check_reinstall()
         self.extract_install()
-        self.store_pisi_files()
 
+        ctx.disable_keyboard_interrupts()
+        self.store_pisi_files()
         self.postinstall()
 
         txn = ctx.dbenv.txn_begin()