[CentOS] DRBD very slow....
Coert Waagmeester
lgroups at waagmeester.co.za
Mon Jul 27 20:09:15 UTC 2009
On Mon, 2009-07-27 at 12:37 +0200, Coert Waagmeester wrote:
> On Mon, 2009-07-27 at 12:02 +0200, Alexander Dalloz wrote:
> > >
> > > On Mon, 2009-07-27 at 08:30 +0200, Coert Waagmeester wrote:
> >
> > >> Hello Roman,
> > >>
> > >> I am running drbd 8.2.6 (the standard centos version)
> >
> >
> > Hi,
> >
> > have you considered to test the drbd-8.3 packages?
> >
> > http://bugs.centos.org/view.php?id=3598
> >
> > http://dev.centos.org/centos/5/testing/{i386,x86_64}/RPMS/
> >
> > Best regards
> >
> > Alexander
> >
> >
> >
> > _______________________________________________
> > CentOS mailing list
> > CentOS at centos.org
> > http://lists.centos.org/mailman/listinfo/centos
>
> Thank you very much for this tip! It was one very obvious place where I
> did not look yet.
>
>
> Would it be necessary to still recompile it for the TCP_NODELAY and
> such?
>
> I am just making sure, because
> http://www.nabble.com/Huge-latency-issue-with-8.2.6-td18947965.html
> makes it seem unnecessary.
>
> Why do the repositories provide both DRBD 8.0.x and 8.2.6?
>
> Thank you all again,
> Coert
>
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
Hello all,
Here is a status update....
_______________________________________________________________________________
on both hosts I now run from the testing repository:
# rpm -qa | grep drbd
drbd83-8.3.1-5.el5.centos
kmod-drbd83-xen-8.3.1-4.el5.centos
_______________________________________________________________________________
Here is my config (slightly condensed):
-----------------------------------------------------
global {
usage-count yes;
}
common {
protocol C;
syncer { rate 50M; }
net {
# allow-two-primaries; }
sndbuf-size 0; }
# disk {no-disk-flushes;
# no-md-flushes; }
startup { wfc-timeout 0 ; }
}
resource xenfilesrv {
device /dev/drbd1;
disk /dev/vg0/xenfilesrv;
meta-disk internal;
on baldur.mydomain.local {
address 10.99.99.1:7788;
}
on thor.mydomain.local {
address 10.99.99.2:7788;
}
}
resource xenfilesrvdata {
device /dev/drbd2;
disk /dev/vg0/xenfilesrvdata;
meta-disk internal;
on baldur.mydomain.local {
address 10.99.99.1:7789;
}
on thor.mydomain.local {
address 10.99.99.2:7789;
}
}
_______________________________________________________________________________
xenfilesrv is a xen domU
in this domU i ran a dd with oflag direct:
---------------------------------------------------------
# dd if=/dev/zero of=1gig.file bs=1M count=1000 oflag=direct
1000+0 records in
1000+0 records out
1048576000 bytes (1.0 GB) copied, 147.997 seconds, 7.1 MB/s
Just before I ran the dd this popped up in the secondary hosts syslog:
----------------------------------------------------------------------
Jul 27 21:51:42 thor kernel: drbd2: Method to ensure write ordering:
flush
Jul 27 21:51:42 thor kernel: drbd1: Method to ensure write ordering:
flush
_______________________________________________________________________________
What more can I try?
To be quite honest, I have no idea what to do with/ where to find the
TCP_NODELAY socket options......
Kind regards,
Coert
More information about the CentOS
mailing list