Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
I have 2 drbd resources shared between 2 IBM x3500 M2 servers.
Storage is composed by 6x146GB 15k RPM SAS driver connected to a
Serveraid MR10i (with BBU and writeback enabled)
Each resource has a dedicated dual gigabit bonding (balance-rr).
Testing the network speed with iperf I have ~ 1.9 Gbit/s on both links
Testing the drbd resources in disconnected mode I have:
[root at srvha01 ~]# dd if=/dev/zero of=/datastore1/test bs=1024k
count=1000 oflag=direct
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 3.6059 seconds, 291 MB/s
Doing the same with the drbd device connected I hardly reach 100 MB/s
So where's the bottleneck?
OS is CentOS 5.3 x86_64 and drbd version is 8.2
drbd.conf follows:
global {
usage-count no;
}
common {
syncer {
rate 700000K;
al-extents 257;
verify-alg md5;
}
protocol C;
handlers {
pri-on-incon-degr "echo b > /proc/sysrq-trigger ; reboot -f";
pri-lost-after-sb "echo b > /proc/sysrq-trigger ; reboot -f";
pri-lost "echo b > /proc/sysrq-trigger ; reboot -f";
local-io-error "echo b > /proc/sysrq-trigger ; reboot -f";
outdate-peer "/usr/lib64/heartbeat/drbd-peer-outdater -t 5";
}
startup {
# wfc-timeout 0;
degr-wfc-timeout 120; # 2 minutes.
# wait-after-sb;
# become-primary-on both;
}
disk {
on-io-error detach;
fencing resource-only;
no-disk-flushes;
no-md-flushes;
}
net {
# max-buffers 20480;
# max-epoch-size 16384;
# unplug-watermark 128;
sndbuf-size 1M;
after-sb-0pri discard-zero-changes;
after-sb-1pri discard-secondary;
after-sb-2pri call-pri-lost-after-sb;
rr-conflict call-pri-lost;
}
}
resource drbd1 {
on srvha01.croceitaliamarche.it {
device /dev/drbd1;
disk /dev/sda3;
address 10.20.30.1:7788;
meta-disk internal;
}
on srvha02.croceitaliamarche.it {
device /dev/drbd1;
disk /dev/sda3;
address 10.20.30.2:7788;
meta-disk internal;
}
}
resource drbd2 {
on srvha01.croceitaliamarche.it {
device /dev/drbd2;
disk /dev/sda4;
address 10.20.30.5:7789;
meta-disk internal;
}
on srvha02.croceitaliamarche.it {
device /dev/drbd2;
disk /dev/sda4;
address 10.20.30.6:7789;
meta-disk internal;
}
}
Thanks in advance
--
Cristian Mammoli
APRA SISTEMI srl
Via Brodolini,6 Jesi (AN)
tel dir. 0731 719822
Web www.apra.it
e-mail c.mammoli at apra.it