[pve-devel] [PATCH] rbdplugin : disable debug_ms to increase performance

[Alexandre Derumier]

This increase iops and decrease latencies by around 30%

debus_ms=1 (current)
--------------------
test: (groupid=0, jobs=1): err= 0: pid=1222: Sat Nov  5 10:04:23 2016
  read : io=15360MB, bw=127472KB/s, iops=31867, runt=123389msec
    slat (usec): min=1, max=9774, avg= 5.91, stdev=16.19
    clat (usec): min=147, max=398690, avg=2000.78, stdev=4521.22
     lat (usec): min=174, max=398707, avg=2006.87, stdev=4521.26
    clat percentiles (usec):
     |  1.00th=[  434],  5.00th=[  764], 10.00th=[  988], 20.00th=[ 1224],
     | 30.00th=[ 1352], 40.00th=[ 1448], 50.00th=[ 1544], 60.00th=[ 1656],
     | 70.00th=[ 1816], 80.00th=[ 2096], 90.00th=[ 3024], 95.00th=[ 4640],
     | 99.00th=[ 8640], 99.50th=[10560], 99.90th=[16192], 99.95th=[25216],
     | 99.99th=[203776]

debug_ms=0
----------
test: (groupid=0, jobs=1): err= 0: pid=1423: Sat Nov  5 09:59:25 2016
  read : io=15360MB, bw=176625KB/s, iops=44156, runt= 89051msec
    slat (usec): min=2, max=8995, avg= 6.70, stdev=11.06
    clat (usec): min=59, max=444656, avg=1438.46, stdev=4094.54
     lat (usec): min=156, max=444660, avg=1446.29, stdev=4094.56
    clat percentiles (usec):
     |  1.00th=[  290],  5.00th=[  498], 10.00th=[  636], 20.00th=[  796],
     | 30.00th=[  900], 40.00th=[  972], 50.00th=[ 1048], 60.00th=[ 1128],
     | 70.00th=[ 1240], 80.00th=[ 1432], 90.00th=[ 2192], 95.00th=[ 3664],
     | 99.00th=[ 7584], 99.50th=[ 9408], 99.90th=[14784], 99.95th=[19840],
     | 99.99th=[203776]
    bw (KB  /s): min=22094, max=232384, per=100.00%, avg=176976.30,

Signed-off-by: Alexandre Derumier <aderumier at odiso.com>
---
 PVE/Storage/RBDPlugin.pm | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/PVE/Storage/RBDPlugin.pm b/PVE/Storage/RBDPlugin.pm
index c1f88e4..6459f98 100644
--- a/PVE/Storage/RBDPlugin.pm
+++ b/PVE/Storage/RBDPlugin.pm
@@ -326,6 +326,8 @@ sub path {
 	$path .= ":auth_supported=none";
     }
 
+    $path .= ":debug_ms=0/0";
+
     my $cephconfig = "/etc/pve/priv/ceph/${storeid}.conf";
 
     if (-e $cephconfig) {
-- 
2.1.4