<br><font size=2 face="sans-serif">Hi All,</font>
<br>
<br><font size=2 face="sans-serif">I have 2 IBM I series server using Linux</font>
<br>
<br><font size=2 face="sans-serif">The drbd 0.7.19 version is install on
them.</font>
<br><font size=2 face="sans-serif">the 2 server are running on a 10mb lines
in a wan configuration</font>
<br>
<br><font size=2 face="sans-serif">The thing I would like to do is explain
in detail what's happenning and the way I see it.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
1 - all_extents,protocol and snd_buffer parameter have been changed</font><font size=3>
</font><font size=2 face="sans-serif"><br>
2 - Take drbd down and back up on both side( to make sure the changed have
take effect)</font><font size=3> </font><font size=2 face="sans-serif"><br>
3 - Start a copy of a 300MB files on the partition /dev/drbd2</font><font size=3>
</font><font size=2 face="sans-serif"><br>
4 - The copy goes all the way</font><font size=3> </font><font size=2 face="sans-serif"><br>
5 - After about 30 sec to 1 minute when the copy finish we can't have access
to the /dev/drbd2 partition (true win samba or just doing a ls of the partition)</font><font size=3>
</font><font size=2 face="sans-serif"><br>
all the other drbd partition and the system it self
show no degradation.</font><font size=3> </font><font size=2 face="sans-serif"><br>
6 - We see in the cat /proc/drbd the bytes of this partition going from
primary to secondary</font><font size=3> </font><font size=2 face="sans-serif"><br>
7 - When the copy is done from primary to secondary the partition /dev/drbd2
become back available and performance is</font><font size=3> </font><font size=2 face="sans-serif"><br>
back to normal on this partition(no other part of
the linux system is affect by this)</font><font size=3> <br>
<br>
</font><font size=2 face="sans-serif"><br>
So what I see in all this.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
It look like drbd doesn't really do is copy from primary to secondary in
the background.</font><font size=3> </font><font size=2 face="sans-serif"><br>
My impression was that drbd would complete is copy in the backround with
out slowing down the access to the fs on the primary machine.</font><font size=3>
</font><font size=2 face="sans-serif"><br>
I really hope this is not a concept issue.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
If I copy let say a 500MB files the same thing happen except it happen
even before the copy to the primary finish</font><font size=3> </font><font size=2 face="sans-serif"><br>
and it can even abort the copy.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
Im really suprise this thing didn't pop up before in drbd forum.</font><font size=3>
</font><font size=2 face="sans-serif"><br>
To me it's basic.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
I really hope there is a parameter somewhere that would fix this.</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
The way I see it, it's really a drbd problem cause the system itself still
response very good.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
It's really the partition that hang until it complete a copy from primary
to secondary.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
All the other partition under drbd doesn't hang.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
To make all parition hang I would just copy 3 files in each partition and
I would be able to hang all</font><font size=3> </font><font size=2 face="sans-serif"><br>
the drbd partition at once.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
They would only get available when the copy from primary to secondary complete.</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
Can you imagine in a production environment having 10 users copying some
1G files to the drbd partitions.</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
Below is the drbd.conf present on both machine.</font><font size=3> <br>
<br>
</font><font size=2 face="sans-serif"><br>
global {</font><font size=3> </font><font size=2 face="sans-serif"><br>
minor-count 4;</font><font size=3> </font><font size=2 face="sans-serif"><br>
dialog-refresh 600;</font><font size=3> </font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
resource drbd0 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
protocol A;</font><font size=3> </font><font size=2 face="sans-serif"><br>
incon-degr-cmd "/bin/true";</font><font size=3>
</font><font size=2 face="sans-serif"><br>
syncer {</font><font size=3> </font><font size=2 face="sans-serif"><br>
rate 70M;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
al-extents 257;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
net {</font><font size=3> </font><font size=2 face="sans-serif"><br>
sndbuf-size 512k;</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
on smb-mtl01 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
device /dev/drbd0;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
disk /dev/mapper/VGPrivate_orion-LVPrivate_orion;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
address 10.10.1.3:7789;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
meta-disk /dev/sdh1[0];</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
on smb-sjo01 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
device /dev/drbd0;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
disk /dev/mapper/VGPrivate_orion-LVPrivate_orion;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
address 10.10.2.66:7789;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
meta-disk /dev/sde1[0];</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
resource drbd1 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
protocol A;</font><font size=3> </font><font size=2 face="sans-serif"><br>
incon-degr-cmd "/bin/true";</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
syncer {</font><font size=3> </font><font size=2 face="sans-serif"><br>
rate 70M;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
al-extents 257;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
net {</font><font size=3> </font><font size=2 face="sans-serif"><br>
sndbuf-size 512k;</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
on smb-mtl01 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
device /dev/drbd1;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
disk /dev/mapper/VGProfiles_orion-LVProfiles_orion;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
address 10.10.1.3:7790;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
meta-disk /dev/sdh1[1];</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
on smb-sjo01 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
device /dev/drbd1;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
disk /dev/mapper/VGProfiles_orion-LVProfiles_orion;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
address 10.10.2.66:7790;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
meta-disk /dev/sde1[1];</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
resource drbd2 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
protocol A;</font><font size=3> </font><font size=2 face="sans-serif"><br>
incon-degr-cmd "/bin/true";</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
syncer {</font><font size=3> </font><font size=2 face="sans-serif"><br>
rate 70M;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
al-extents 257;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
net {</font><font size=3> </font><font size=2 face="sans-serif"><br>
sndbuf-size 512k;</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
on smb-mtl01 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
device /dev/drbd2;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
disk /dev/mapper/VGPublic_orion-LVPublic_orion;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
address 10.10.1.3:7791;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
meta-disk /dev/sdh1[2];</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
on smb-sjo01 {</font><font size=3> </font><font size=2 face="sans-serif"><br>
device /dev/drbd2;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
disk /dev/mapper/VGPublic_orion-LVPublic_orion;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
address 10.10.2.66:7791;</font><font size=3>
</font><font size=2 face="sans-serif"><br>
meta-disk /dev/sde1[2];</font><font size=3>
</font><font size=2 face="sans-serif"><br>
}</font><font size=3> </font><font size=2 face="sans-serif"><br>
}</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
Hope we can find a solution to this</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
Thanks !</font><font size=3> </font>
<br>
<br>
<br>
<br><font size=2 face="sans-serif">Claude Pelletier<br>
Serti Informatique Inc.<br>
Courriel/Email : cpelletier@serti.com<br>
Téléphone/Phone : (514) 493-1909<br>
Télécopieur/Fax : (514) 493-3575<br>
</font>