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

[Alexandre Derumier]

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