[DRBD-user] Disk I/O direct vs. Drbd

roberto.fastec at gmail.com roberto.fastec at gmail.com
Fri Aug 13 12:03:20 CEST 2010


My drbd replication channel is dedicated crossovered gigabit nic

Thank you for any confirmation.

Robert
Le mail ti raggiungono ovunque con BlackBerry® from Vodafone!

-----Original Message-----
From: drbd-user-request at lists.linbit.com
Sender: drbd-user-bounces at lists.linbit.com
Date: Fri, 13 Aug 2010 12:00:02 
To: <drbd-user at lists.linbit.com>
Reply-To: drbd-user at lists.linbit.com
Subject: drbd-user Digest, Vol 73, Issue 15

Send drbd-user mailing list submissions to
	drbd-user at lists.linbit.com

To subscribe or unsubscribe via the World Wide Web, visit
	http://lists.linbit.com/mailman/listinfo/drbd-user
or, via email, send a message with subject or body 'help' to
	drbd-user-request at lists.linbit.com

You can reach the person managing the list at
	drbd-user-owner at lists.linbit.com

When replying, please edit your Subject line so it is more specific
than "Re: Contents of drbd-user digest..."


Today's Topics:

   1. Re: Initial sync,	just want to confirm the process (and not
      go down in a blaze	of	glory) (Simon Billis)
   2. Re: Initial sync,	just want to confirm the process (and not
      go down in a	blaze	of	glory) (Simon Billis)
   3. Disk I/O direct vs. Drbd (roberto.fastec at gmail.com)
   4. Re: Disk I/O direct vs. Drbd (Bart Coninckx)


----------------------------------------------------------------------

Message: 1
Date: Fri, 13 Aug 2010 09:24:22 +0100
From: "Simon Billis" <simon at houxou.com>
Subject: Re: [DRBD-user] Initial sync,	just want to confirm the
	process (and not go down in a blaze	of	glory)
To: "'Lars Ellenberg'" <lars.ellenberg at linbit.com>,
	<drbd-user at lists.linbit.com>
Message-ID: <00ce01cb3ac0$ef21e960$cd65bc20$@com>
Content-Type: text/plain;	charset="iso-8859-1"

Lars Ellenberg sent a missive on?2010-08-13:

> On Fri, Aug 13, 2010 at 07:00:50AM +0100, Simon Billis wrote:
>> Hi,
>>> Subject: Re: [DRBD-user] Initial sync, just want to confirm the
>>> process (and not go down in a blaze of glory)
>>> 
>>> Hmm sorry Dan, but this has left me a little confused. As I said in my
>>> first post, storage00 is LIVE and has around 4TB of data on it, I have
>>> a dedicated gigabit NIC for drbd, (the machine has 6 network cards in
>>> it, 4 for MPIO iSCSI, 1 for managment/heartbeat, 1 for DRBD) I have
>>> already setup storage01 and have issued drbdadm create-md meta and
>>> drbdadm create-md data on the secondary machine, I haven't started
>>> drbd on it as it needs to be rebooted first, hence why I'm now a
>>> little cautious on the reboot of the machine.
>> 
>> I'm not sure why you will need to reboot, you should be able to
>> bring the drbd resource into secondary mode right away with the
>> following commands
>> 
>> #On the primary node (storage00) check the status with drbdadm
>> status
>> 
>> #You should see something like:
>> [root at raid-primary ~]# drbdadm status <drbd-status version="8.3.8"
>> api="88"> <resources config_file="/etc/drbd.conf"> <resource
>> minor="1" name="drbd1"
>> cs="StandAlone" ro1="Primary" ro2="Unknown"
>> ds1="UpToDate" ds2="DUnknown" />
> 
> Uh.
> 
> !?
> 
> Why would you voluntarily parse pseudo-xml with your eyes?
> That output is meant to be consumed by scripts or the DRBD MC Gui.
> 
> Try:
> # drbd-overview
> or
> # cat /proc/drbd
> or
> # grep cs: /proc/drbd
>

Thanks for the suggestion - I agree it's easier to read. Live and learn :-) 






------------------------------

Message: 2
Date: Fri, 13 Aug 2010 09:27:55 +0100
From: "Simon Billis" <simon at houxou.com>
Subject: Re: [DRBD-user] Initial sync,	just want to confirm the
	process (and not go down in a	blaze	of	glory)
To: "'Simon Billis'" <simon at houxou.com>,	"'Lars Ellenberg'"
	<lars.ellenberg at linbit.com>,	<drbd-user at lists.linbit.com>
Message-ID: <00cf01cb3ac1$6e19e100$4a4da300$@com>
Content-Type: text/plain;	charset="iso-8859-1"

Simon Billis sent a missive on?2010-08-13:

> Lars Ellenberg sent a missive on?2010-08-13:
>>> #You should see something like:
>>> [root at raid-primary ~]# drbdadm status <drbd-status version="8.3.8"
>>> api="88"> <resources config_file="/etc/drbd.conf"> <resource
>>> minor="1" name="drbd1"
>>> cs="StandAlone" ro1="Primary" ro2="Unknown"
>>> ds1="UpToDate" ds2="DUnknown" />
>> 
>> Uh.
>> 
>> !?
>> 
>> Why would you voluntarily parse pseudo-xml with your eyes?
>> That output is meant to be consumed by scripts or the DRBD MC Gui.
>> 
>> Try:
>> # drbd-overview
>> or
>> # cat /proc/drbd
>> or
>> # grep cs: /proc/drbd
>> 
> 
> Thanks for the suggestion - I agree it's easier to read. Live and learn
> :-)

I guess that it comes from using earlier versions of drbd than 8 :-) - just
goes to show RTFM ;-)






------------------------------

Message: 3
Date: Fri, 13 Aug 2010 08:42:13 +0000
From: roberto.fastec at gmail.com
Subject: [DRBD-user] Disk I/O direct vs. Drbd
To: drbd-user at lists.linbit.com
Message-ID:
	<1936187021-1281688929-cardhu_decombobulator_blackberry.rim.net-1512612866- at bda035.bisx.produk.on.blackberry>
	
Content-Type: text/plain; charset="Windows-1252"

In my linux system, I/O expecially write speed is 90MB/sec

Installing drbd makes it slow to 30MB/sec.

I suppose that drbd tracking and logs processes are obviously write and read consumers.

My question is if you confirm that this ratio 90MB/sec that slows  to 30 is to be considered as expected with drbd in between.

The configuration of both the pcs is 1 sata drive for linux and 1 sata drive for drbd.

Please also note that I have not set any value for al-extents.

Thank you
Robert
Le mail ti raggiungono ovunque con BlackBerry? from Vodafone!

------------------------------

Message: 4
Date: Fri, 13 Aug 2010 10:47:49 +0200
From: Bart Coninckx <bart.coninckx at telenet.be>
Subject: Re: [DRBD-user] Disk I/O direct vs. Drbd
To: drbd-user at lists.linbit.com, roberto.fastec at gmail.com
Message-ID: <201008131047.49813.bart.coninckx at telenet.be>
Content-Type: Text/Plain;  charset="windows-1252"

On Friday 13 August 2010 10:42:13 roberto.fastec at gmail.com wrote:
> In my linux system, I/O expecially write speed is 90MB/sec
> 
> Installing drbd makes it slow to 30MB/sec.
> 
> I suppose that drbd tracking and logs processes are obviously write and
>  read consumers.
> 
> My question is if you confirm that this ratio 90MB/sec that slows  to 30 is
>  to be considered as expected with drbd in between.
> 
> The configuration of both the pcs is 1 sata drive for linux and 1 sata
>  drive for drbd.
> 
> Please also note that I have not set any value for al-extents.
> 
> Thank you
> Robert
> Le mail ti raggiungono ovunque con BlackBerry? from Vodafone!
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user
> 

That is way too slow. What is your network situation in between the two?  


------------------------------

_______________________________________________
drbd-user mailing list
drbd-user at lists.linbit.com
http://lists.linbit.com/mailman/listinfo/drbd-user


End of drbd-user Digest, Vol 73, Issue 15
*****************************************


More information about the drbd-user mailing list