[pve-devel] vm stop tasks hanging

Alexandre DERUMIER aderumier at odiso.com
Fri Apr 20 17:24:58 CEST 2012


it's possible to filter at command line like this:

(exemple for scanning /dev/sda only)

/sbin/lvs --config 'devices { filter = [ "a|^/dev/sda$|", "r/.*/" ] }' --separator : --noheadings --units b --unbuffered --nosuffix --options vg_name,lv_name,lv_size,uuid,tags

maybe can we pass device to lvm_lvs () ?


----- Mail original ----- 

De: "Alexandre DERUMIER" <aderumier at odiso.com> 
À: "Dietmar Maurer" <dietmar at proxmox.com> 
Cc: pve-devel at pve.proxmox.com 
Envoyé: Vendredi 20 Avril 2012 16:15:03 
Objet: Re: [pve-devel] vm stop tasks hanging 

I didn't know good this part of code, 
but yes It can be better. 

Also, is it possible to restrict "/sbin/lvs --separator ...." to a specific device ? 

I think we could do it in /etc/lvm/lvm.conf 

# By default we accept every block device: 
filter = [ "a/.*/" ] 

maybe can we update this file with device with lvm partitions ? (maybe this is hard to implement....) 


----- Mail original ----- 

De: "Dietmar Maurer" <dietmar at proxmox.com> 
À: "Alexandre DERUMIER" <aderumier at odiso.com> 
Cc: pve-devel at pve.proxmox.com 
Envoyé: Vendredi 20 Avril 2012 15:58:26 
Objet: RE: [pve-devel] vm stop tasks hanging 

Better, but maybe we can only call it if the device is activated? 

> -----Original Message----- 
> From: Alexandre DERUMIER [mailto:aderumier at odiso.com] 
> Sent: Freitag, 20. April 2012 15:09 
> To: Dietmar Maurer 
> Cc: pve-devel at pve.proxmox.com 
> Subject: Re: [pve-devel] vm stop tasks hanging 
> 
> what do you think about this: 
> only call lvm_lvs, once only, if storage is lvm. 
> 
> 
> 
> sub deactivate_volumes { 
> my ($cfg, $vollist) = @_; 
> 
> return if !($vollist && scalar(@$vollist)); 
> 
> >> my $lvs=undef; 
> my @errlist = (); 
> foreach my $volid (@$vollist) { 
> my ($storeid, $volname) = parse_volume_id ($volid); 
> 
> my $scfg = storage_config ($cfg, $storeid); 
> 
> if ($scfg->{type} eq 'lvm') { 
> my ($name) = parse_volname_lvm ($volname); 
> >> $lvs = lvm_lvs () if !$lvs; 
> 
> if ($lvs->{$scfg->{vgname}}->{$name}) { 
> my $path = path ($cfg, $volid); 
> my $cmd = ['/sbin/lvchange', '-aln', $path]; 
> eval { run_command($cmd, errmsg => "can't deactivate LV '$volid'"); 
> }; 
> if (my $err = $@) { 
> warn $err; 
> push @errlist, $volid; 
> } 
> } 
> } 
> } 
> 
> die "volume deativation failed: " . join(' ', @errlist) 
> if scalar(@errlist); 
> } 
> 
> 
> ----- Mail original ----- 
> 
> De: "Alexandre DERUMIER" <aderumier at odiso.com> 
> À: "Dietmar Maurer" <dietmar at proxmox.com> 
> Cc: pve-devel at pve.proxmox.com 
> Envoyé: Vendredi 20 Avril 2012 13:08:13 
> Objet: Re: [pve-devel] vm stop tasks hanging 
> 
> I had launched the command 
> /sbin/lvs --separator : --noheadings --units b --unbuffered --nosuffix -- 
> options vg_name,lv_name,lv_size,uuid,tags 
> 
> it take around 60sec to parse all my disks on a test server 
> 
> But I don't understand why it hang when called on my production server. 
> 
> Maybe I have a hanging disk lun on my production server... 
> 
> Do we really need to rescan lvm before desactivate volumes ? 
> 
> what happen if we remove: 
> 
> my $lvs = lvm_lvs () 
> if ($lvs->{$scfg->{vgname}}->{$name}) { 
> 
> ? 
> 
> (I don't have lvm disks to test for the moment...) 
> 
> 
> ----- Mail original ----- 
> 
> De: "Dietmar Maurer" <dietmar at proxmox.com> 
> À: "Alexandre DERUMIER" <aderumier at odiso.com>, "Stefan Priebe - 
> Profihost AG" <s.priebe at profihost.ag> 
> Cc: pve-devel at pve.proxmox.com 
> Envoyé: Vendredi 20 Avril 2012 12:28:32 
> Objet: RE: [pve-devel] vm stop tasks hanging 
> 
> Maybe. I do not have such setup, so its hard to test here. 
> 
> > -----Original Message----- 
> > From: pve-devel-bounces at pve.proxmox.com [mailto:pve-devel- 
> > bounces at pve.proxmox.com] On Behalf Of Alexandre DERUMIER 
> > Sent: Freitag, 20. April 2012 12:23 
> > To: Stefan Priebe - Profihost AG 
> > Cc: pve-devel at pve.proxmox.com 
> > Subject: Re: [pve-devel] vm stop tasks hanging 
> > 
> > also, I have around 600luns, so maybe lvs try to scan each of them ? 
> > 
> > ----- Mail original ----- 
> > 
> > De: "Alexandre DERUMIER" <aderumier at odiso.com> 
> > À: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
> > Cc: pve-devel at pve.proxmox.com 
> > Envoyé: Vendredi 20 Avril 2012 12:03:43 
> > Objet: Re: [pve-devel] vm stop tasks hanging 
> > 
> > I think I found the problem: 
> > 
> > in Qemuserver.pm : vm_stop_cleanup sub 
> > 
> > -> PVE::Storage::deactivate_volumes($storecfg, $vollist); 
> > 
> > 
> > sub deactivate_volumes { 
> > my ($cfg, $vollist) = @_; 
> > 
> > return if !($vollist && scalar(@$vollist)); 
> > 
> > my $lvs = lvm_lvs (); ------------------------------> this is called, 
> > but I don't use lvm 
> > 
> > my @errlist = (); 
> > foreach my $volid (@$vollist) { 
> > my ($storeid, $volname) = parse_volume_id ($volid); 
> > 
> > my $scfg = storage_config ($cfg, $storeid); 
> > 
> > if ($scfg->{type} eq 'lvm') { 
> > my ($name) = parse_volname_lvm ($volname); 
> > 
> > if ($lvs->{$scfg->{vgname}}->{$name}) { my $path = path ($cfg, 
> > $volid); my $cmd = ['/sbin/lvchange', '-aln', $path]; eval { 
> > run_command($cmd, errmsg => "can't deactivate LV '$volid'"); }; if (my 
> > $err = $@) { warn $err; push @errlist, $volid; } } } } 
> > 
> > die "volume deativation failed: " . join(' ', @errlist) 
> > 
> > 
> > sub lvm_lvs { 
> > my ($vgname) = @_; 
> > 
> > my $cmd = ['/sbin/lvs', '--separator', ':', '--noheadings', '--units', 
> > 'b', '--unbuffered', '--nosuffix', '--options', 
> > 'vg_name,lv_name,lv_size,uuid,tags']; 
> > 
> > 
> > 
> > 
> > maybe adding a 
> > 
> > return if $scfg->{type} ne 'lvm' 
> > 
> > at the begin of deactivate_volumes sub should help ? 
> > 
> > 
> > ----- Mail original ----- 
> > 
> > De: "Alexandre DERUMIER" <aderumier at odiso.com> 
> > À: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
> > Cc: pve-devel at pve.proxmox.com 
> > Envoyé: Vendredi 20 Avril 2012 10:39:13 
> > Objet: Re: [pve-devel] vm stop tasks hanging 
> > 
> > interesting: when I stop the process, I have this error: 
> > 
> > 
> > command '/sbin/lvs --separator : --noheadings --units b --unbuffered 
> > -- nosuffix --options vg_name,lv_name,lv_size,uuid,tags' failed: 
> > received interrupt root at kvm6:~# 
> > 
> > I'm using scsi lun directly without lvm, maybe this is the cause of 
> > the problem ? 
> > 
> > 
> > 
> > ----- Mail original ----- 
> > 
> > De: "Alexandre DERUMIER" <aderumier at odiso.com> 
> > À: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
> > Cc: pve-devel at pve.proxmox.com 
> > Envoyé: Vendredi 20 Avril 2012 10:36:37 
> > Objet: Re: [pve-devel] vm stop tasks hanging 
> > 
> > Hi, 
> > console or proxmox gui, same problem. 
> > 
> > strace : 
> > 
> > Process 536632 attached - interrupt to quit select(8, [6], NULL, NULL, 
> > {0, 602921}) = 0 (Timeout) open("/proc/536638/stat", O_RDONLY) = 10 
> > ioctl(10, SNDCTL_TMR_TIMEBASE or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY 
> > (Inappropriate ioctl for device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, 
> > {st_mode=S_IFREG|0444, st_size=0, ...}) = 0 fcntl(10, F_SETFD, 
> > FD_CLOEXEC) = 0 read(10, "536638 (qm) S 536632 536638 5366"..., 4096) 
> > = 263 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 263 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 263 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}) = 0 (Timeout) 
> > open("/proc/536638/stat", O_RDONLY) = 10 ioctl(10, 
> SNDCTL_TMR_TIMEBASE 
> > or TCGETS, 0x7fff4daca4b0) = -1 ENOTTY (Inappropriate ioctl for 
> > device) lseek(10, 0, SEEK_CUR) = 0 fstat(10, {st_mode=S_IFREG|0444, 
> > st_size=0, ...}) = 0 fcntl(10, F_SETFD, FD_CLOEXEC) = 0 read(10, 
> > "536638 (qm) S 536632 536638 5366"..., 4096) = 262 
> > close(10) = 0 
> > select(8, [6], NULL, NULL, {1, 0}^C <unfinished ...> Process 536632 
> > detached 
> > 
> > 
> > ----- Mail original ----- 
> > 
> > De: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
> > À: pve-devel at pve.proxmox.com 
> > Envoyé: Vendredi 20 Avril 2012 10:00:50 
> > Objet: Re: [pve-devel] vm stop tasks hanging 
> > 
> > Am 20.04.2012 09:58, schrieb Alexandre DERUMIER: 
> > > Hi Dietmar, 
> > > 
> > > I have problems with kvm stopping task, which are hanging. 
> > > 
> > > vm stop correctly (icon in tree is black), but task continue to run. 
> > > (so i need 
> > to stop the task manually). 
> > > 
> > > I can reproduce it 100%. 
> > > 
> > > Do you have an idea ? 
> > 
> > What does an strace -f -p PID of the vm stop command say? It should do 
> > or wait for something. Also does it only happen via Proxmox console or 
> > does it also happen when starting then command via shell? 
> > 
> > Greets 
> > Stefan 
> > _______________________________________________ 
> > pve-devel mailing list 
> > pve-devel at pve.proxmox.com 
> > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel 
> > 
> > 
> > 
> > -- 
> > 
> > -- 
> > 
> > 
> > 
> > 
> > Alexandre D erumier 
> > Ingénieur Système 
> > Fixe : 03 20 68 88 90 
> > Fax : 03 20 68 90 81 
> > 45 Bvd du Général Leclerc 59100 Roubaix - France 
> > 12 rue Marivaux 75002 Paris - France 
> > 
> > 
> > 
> > 
> > -- 
> > 
> > -- 
> > 
> > 
> > 
> > 
> > Alexandre D erumier 
> > Ingénieur Système 
> > Fixe : 03 20 68 88 90 
> > Fax : 03 20 68 90 81 
> > 45 Bvd du Général Leclerc 59100 Roubaix - France 
> > 12 rue Marivaux 75002 Paris - France 
> > 
> > _______________________________________________ 
> > pve-devel mailing list 
> > pve-devel at pve.proxmox.com 
> > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel 
> > 
> > 
> > 
> > -- 
> > 
> > -- 
> > 
> > 
> > 
> > 
> > Alexandre D erumier 
> > Ingénieur Système 
> > Fixe : 03 20 68 88 90 
> > Fax : 03 20 68 90 81 
> > 45 Bvd du Général Leclerc 59100 Roubaix - France 
> > 12 rue Marivaux 75002 Paris - France 
> > 
> > _______________________________________________ 
> > pve-devel mailing list 
> > pve-devel at pve.proxmox.com 
> > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel 
> > 
> > 
> > 
> > -- 
> > 
> > -- 
> > 
> > 
> > 
> > 
> > Alexandre D erumier 
> > Ingénieur Système 
> > Fixe : 03 20 68 88 90 
> > Fax : 03 20 68 90 81 
> > 45 Bvd du Général Leclerc 59100 Roubaix - France 
> > 12 rue Marivaux 75002 Paris - France 
> > 
> > _______________________________________________ 
> > pve-devel mailing list 
> > pve-devel at pve.proxmox.com 
> > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel 
> 
> 
> 
> -- 
> 
> -- 
> 
> 
> 
> 
> Alexandre D erumier 
> Ingénieur Système 
> Fixe : 03 20 68 88 90 
> Fax : 03 20 68 90 81 
> 45 Bvd du Général Leclerc 59100 Roubaix - France 
> 12 rue Marivaux 75002 Paris - France 
> 
> _______________________________________________ 
> pve-devel mailing list 
> pve-devel at pve.proxmox.com 
> http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel 
> 
> 
> 
> -- 
> 
> -- 
> 
> 
> 
> 
> Alexandre D erumier 
> Ingénieur Système 
> Fixe : 03 20 68 88 90 
> Fax : 03 20 68 90 81 
> 45 Bvd du Général Leclerc 59100 Roubaix - France 
> 12 rue Marivaux 75002 Paris - France 
> 




-- 

-- 




Alexandre D erumier 
Ingénieur Système 
Fixe : 03 20 68 88 90 
Fax : 03 20 68 90 81 
45 Bvd du Général Leclerc 59100 Roubaix - France 
12 rue Marivaux 75002 Paris - France 

_______________________________________________ 
pve-devel mailing list 
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http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel 



-- 

-- 




	Alexandre D erumier 
Ingénieur Système 
Fixe : 03 20 68 88 90 
Fax : 03 20 68 90 81 
45 Bvd du Général Leclerc 59100 Roubaix - France 
12 rue Marivaux 75002 Paris - France 
	



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