sudo apt-get update está demorando muito tempo após atualizar o software do centro de software no ubuntu 14.04

Question

tejesh@tejesh-Inspiron-3542:~$ sudo apt-get update
Ign http:// extras.ubuntu.com trusty InRelease
Ign http:// dl.google.com stable InRelease                                      
Hit http:// dl.google.com stable Release.gpg                                    
Ign http:// ppa.launchpad.net trusty InRelease                                  
Hit http:// extras.ubuntu.com trusty Release.gpg                                
Hit http:// archive.canonical.com trusty InRelease                              
Hit http:// dl.google.com stable Release                                        
Ign http:// ppa.launchpad.net trusty InRelease                                  
Hit http:// extras.ubuntu.com trusty Release                                    
Hit http:// dl.google.com stable/main amd64 Packages                            
Hit http:// archive.canonical.com trusty/partner Sources                        
Hit http:// dl.google.com stable/main i386 Packages                             
Ign http:// ppa.launchpad.net trusty InRelease                                  
Hit http:// extras.ubuntu.com trusty/main Sources                               
Hit http:// archive.canonical.com trusty/partner amd64 Packages                 
Ign http:// ppa.launchpad.net trusty InRelease                                  
Hit http:// extras.ubuntu.com trusty/main amd64 Packages                        
Hit http:// archive.canonical.com trusty/partner i386 Packages                  
Ign http:// ppa.launchpad.net trusty InRelease                                  
Hit http:// extras.ubuntu.com trusty/main i386 Packages                         
Hit http:// archive.canonical.com trusty/partner Translation-en                 
Hit http:// ppa.launchpad.net trusty InRelease                                  
Ign http:// ppa.launchpad.net trusty InRelease                                  
Ign http:// dl.google.com stable/main Translation-en_IN                         
Ign http:// dl.google.com stable/main Translation-en                   
Ign http:// ppa.launchpad.net trusty InRelease                         
Ign http:// ppa.launchpad.net trusty InRelease                         
Ign http:// ppa.launchpad.net trusty InRelease   
Ign http:// ppa.launchpad.net trusty InRelease   
Hit http:// ppa.launchpad.net trusty Release.gpg 
Hit http:// ppa.launchpad.net trusty Release.gpg                                
Hit http:// ppa.launchpad.net trusty Release.gpg                                
Ign http:// extras.ubuntu.com trusty/main Translation-en_IN
Hit http:// ppa.launchpad.net trusty Release.gpg 
Ign http:// extras.ubuntu.com trusty/main Translation-en
Hit http:// ppa.launchpad.net trusty Release.gpg 
Hit http:// ppa.launchpad.net trusty/main amd64 Packages
Hit http:// ppa.launchpad.net trusty/main i386 Packages             
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Hit http:// ppa.launchpad.net trusty Release.gpg                                
Hit http:// ppa.launchpad.net trusty Release.gpg 
Ign http:// ppa.launchpad.net trusty Release.gpg
Hit http:// ppa.launchpad.net trusty Release.gpg
Hit http:// ppa.launchpad.net trusty Release.gpg
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Ign http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty Release                                    
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Hit http:// ppa.launchpad.net trusty/main amd64 Packages                        
Hit http:// ppa.launchpad.net trusty/main i386 Packages                         
Hit http:// ppa.launchpad.net trusty/main Translation-en                        
Ign http:// ppa.launchpad.net trusty/main Translation-en_IN                     
Ign http:// ppa.launchpad.net trusty/main Translation-en
Ign http:// ppa.launchpad.net trusty/main Translation-en_IN
Ign http:// ppa.launchpad.net trusty/main Translation-en
Ign http:// ppa.launchpad.net trusty/main Translation-en_IN
Ign http:// ppa.launchpad.net trusty/main Translation-en
Err http:// ppa.launchpad.net trusty/main amd64 Packages
  404  Not Found
Err http:// ppa.launchpad.net trusty/main i386 Packages
  404  Not Found
Ign http:// ppa.launchpad.net trusty/main Translation-en_IN
Ign http:// ppa.launchpad.net trusty/main Translation-en
Ign http:// archive.ubuntu.com trusty InRelease
Hit http:// archive.ubuntu.com trusty-updates InRelease
Hit http:// archive.ubuntu.com trusty-backports InRelease                       
Hit http:// archive.ubuntu.com trusty-security InRelease
Ign http:// archive.ubuntu.com trusty Release.gpg                               
Get:1 http:// archive.ubuntu.com trusty-updates/main Sources [237 kB]
Get:2 http:// archive.ubuntu.com trusty-updates/universe Sources [140 kB]       
Get:3 http:// archive.ubuntu.com trusty-updates/multiverse Sources [5,144 B]    
Get:4 http:// archive.ubuntu.com trusty-updates/main amd64 Packages [627 kB]  
Get:5 http:// archive.ubuntu.com trusty-updates/restricted amd64 Packages [15.4 kB]
Get:6 http:// archive.ubuntu.com trusty-updates/universe amd64 Packages [320 kB]
Get:7 http:// archive.ubuntu.com trusty-updates/multiverse amd64 Packages [11.9 kB]
Get:8 http:// archive.ubuntu.com trusty-updates/main i386 Packages [608 kB]     
Get:9 http:// archive.ubuntu.com trusty-updates/restricted i386 Packages [15.1 kB]
Get:10 http:// archive.ubuntu.com trusty-updates/universe i386 Packages [321 kB]
Get:11 http:// archive.ubuntu.com trusty-updates/multiverse i386 Packages [12.1 kB]
Get:12 http:// archive.ubuntu.com trusty-updates/main Translation-en [304 kB]   
100% [Waiting for headers]                                                     

    

Answer 1

O processo apt-get update foi concluído e as últimas linhas foram as seguintes:

Fetched 15.2 MB in 47min 46s (5,304 B/s) 

W: Failed to fetch ppa .launchpad.net/picaso/octave/ubuntu/dists/trusty/main/… 404 Not Found 

W: Failed to fetch ppa .launchpad.net/picaso/octave/ubuntu/dists/trusty/main/… 404 Not Found 

E: Some index files failed to download. They have been ignored, or old ones used instead. 
tejesh@tejesh-Inspiron-3542:~$

Quando você abrir este aplicativo, o software e as atualizações e a guia "Outros" removerão isso da lista:

ppa .launchpad.net/picaso/octave/ubuntu/dists/trusty/main