[pve-devel] [PATCH] iothreads : create 1 iothread by virtio device

[Alexandre DERUMIER]

I'm also thinking to improve this patch,

with settings iothread as a drive property instead to enable it globally.
Like this we can enable it only on drive which need best performance

(I think that nobody use currently the iothread option)

What do you think about this ?

----- Mail original -----
De: "aderumier" <aderumier at odiso.com>
À: "pve-devel" <pve-devel at pve.proxmox.com>
Cc: "aderumier" <aderumier at odiso.com>
Envoyé: Lundi 12 Janvier 2015 10:56:04
Objet: [PATCH] iothreads : create 1 iothread by virtio device

for better performance, we create 1 iothread "iothread-deviceid" by virtio device. 

we can hot-add|del iothread with object_add|del qmp command 

Benched with rbd : I can reach around 40000iops by iothreads 

Signed-off-by: Alexandre Derumier <aderumier at odiso.com> 
--- 
PVE/QemuServer.pm | 47 ++++++++++++++++++++++++++++++++++++++++++++--- 
1 file changed, 44 insertions(+), 3 deletions(-) 

diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm 
index 0e25148..087c508 100644 
--- a/PVE/QemuServer.pm 
+++ b/PVE/QemuServer.pm 
@@ -1115,7 +1115,7 @@ sub print_drivedevice_full { 
if ($drive->{interface} eq 'virtio') { 
my $pciaddr = print_pci_addr("$drive->{interface}$drive->{index}", $bridges); 
$device = "virtio-blk-pci,drive=drive-$drive->{interface}$drive->{index},id=$drive->{interface}$drive->{index}$pciaddr"; 
- $device .= ",iothread=iothread0" if $conf->{iothread}; 
+ $device .= ",iothread=iothread-$drive->{interface}$drive->{index}" if $conf->{iothread}; 
} elsif ($drive->{interface} eq 'scsi') { 
$maxdev = ($conf->{scsihw} && ($conf->{scsihw} !~ m/^lsi/)) ? 256 : 7; 
my $controller = int($drive->{index} / $maxdev); 
@@ -2616,8 +2616,6 @@ sub config_to_command { 
push @$cmd, '-smbios', "type=1,$conf->{smbios1}"; 
} 

- push @$cmd, '-object', "iothread,id=iothread0" if $conf->{iothread}; 
- 
if ($q35) { 
# the q35 chipset support native usb2, so we enable usb controller 
# by default for this machine type 
@@ -3015,6 +3013,10 @@ sub config_to_command { 
} 
} 

+ if($ds =~ m/^virtio/){ 
+ push @$cmd, '-object', "iothread,id=iothread-$ds" if $conf->{iothread}; 
+ } 
+ 
if ($drive->{interface} eq 'scsi') { 

my $maxdev = ($scsihw !~ m/^lsi/) ? 256 : 7; 
@@ -3165,6 +3167,11 @@ sub vm_deviceplug { 

} elsif ($deviceid =~ m/^(virtio)(\d+)$/) { 

+ if($conf->{iothread}) { 
+ my $iothreads = vm_iothreads_list($vmid); 
+ qemu_objectadd($vmid, "iothread-$deviceid", "iothread") if !$iothreads->{"iothread-$deviceid"}; 
+ } 
+ 
qemu_driveadd($storecfg, $vmid, $device); 
my $devicefull = print_drivedevice_full($storecfg, $conf, $vmid, $device); 

@@ -3246,6 +3253,11 @@ sub vm_deviceunplug { 
qemu_devicedel($vmid, $deviceid); 
qemu_devicedelverify($vmid, $deviceid); 
qemu_drivedel($vmid, $deviceid); 
+ 
+ if($conf->{iothread}) { 
+ my $iothreads = vm_iothreads_list($vmid); 
+ qemu_objectdel($vmid, "iothread-$deviceid") if $iothreads->{"iothread-$deviceid"}; 
+ } 

} elsif ($deviceid =~ m/^(lsi)(\d+)$/) { 

@@ -3269,6 +3281,35 @@ sub vm_deviceunplug { 
return 1; 
} 

+sub vm_iothreads_list { 
+ my ($vmid) = @_; 
+ 
+ my $res = vm_mon_cmd($vmid, 'query-iothreads'); 
+ 
+ my $iothreads = {}; 
+ foreach my $iothread (@$res) { 
+ $iothreads->{ $iothread->{id} } = $iothread->{"thread-id"}; 
+ } 
+ 
+ return $iothreads; 
+} 
+ 
+sub qemu_objectadd { 
+ my($vmid, $objectid, $qomtype) = @_; 
+ 
+ vm_mon_cmd($vmid, "object-add", id => $objectid, "qom-type" => $qomtype); 
+ 
+ return 1; 
+} 
+ 
+sub qemu_objectdel { 
+ my($vmid, $objectid) = @_; 
+ 
+ vm_mon_cmd($vmid, "object-del", id => $objectid); 
+ 
+ return 1; 
+} 
+ 
sub qemu_deviceadd { 
my ($vmid, $devicefull) = @_; 

-- 
1.7.10.4