[DRBD-user] write performance for DRBD devices seems to be slow

Warren Beldad advisory22 at gmail.com
Tue Jul 12 13:27:29 CEST 2005

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.


ok I have here added my iozone results.
I am just new to this drbd maybe a month or two. Does anyone have the
standard benchmark results for drbd or where can i find it? I am
really worried about the write performance on our drbd, the difference
is just too big and much more is if it is now under NFS and samba.

LVM2 + XFS
File size set to 4096 KB
	Record Size 4 KB
	SYNC Mode. 
	Include fsync in write timing
	Include close in write timing
	Command line used: ./iozone -s4m -r4k -o -e -c
	Output is in Kbytes/sec
	Time Resolution = 0.000001 seconds.
	Processor cache size set to 1024 Kbytes.
	Processor cache line size set to 32 bytes.
	File stride size set to 17 * record size.
                                                            random 
random    bkwd  record  stride
              KB  reclen   write rewrite    read    reread    read  
write    read rewrite    read   fwrite frewrite   fread  freread
            4096       4   11680   35386  1126176  1158032  926910  
34997  939673   35074  907599    64502    68108 1016369  1079917

LVM2 + DRBD + XFS
File size set to 4096 KB
	Record Size 4 KB
	SYNC Mode. 
	Include fsync in write timing
	Include close in write timing
	Command line used: ./iozone -s4m -r4k -o -e -c
	Output is in Kbytes/sec
	Time Resolution = 0.000001 seconds.
	Processor cache size set to 1024 Kbytes.
	Processor cache line size set to 32 bytes.
	File stride size set to 17 * record size.
                                                            random 
random    bkwd  record  stride
              KB  reclen   write rewrite    read    reread    read  
write    read rewrite    read   fwrite frewrite   fread  freread
            4096       4     619    5138   520068   516903  460170   
2494  459762    4503  461883    10358     9790 1021212  1003702

thanks, warren

On 7/8/05, Lars Ellenberg <Lars.Ellenberg at linbit.com> wrote:
> / 2005-07-07 20:18:06 +0800
> \ Warren Beldad:
> > Hi all!
> >
> > I have are a simple results of the performance of my drbd test machines.
> > Using the dd command, first I get the performance value of my
> > harddisk. That would be formatting the /dev/sda with XFS and then
> > mount it and then write a 1GB file (which is twice the size of my RAM)
> > into that disk with dd command on different block sizes and then read
> > back that file into the black hole.
> > time dd if=/dev/zero of=testfile.txt bs=512k count=2000
> > time dd if=testfile.txt of=/dev/null bs=512k
> 
> your benchmark is broken.
> man close
> man fsync
> no, dd does not do fsync.
> 
> --
> : Lars Ellenberg                                  Tel +43-1-8178292-0  :
> : LINBIT Information Technologies GmbH            Fax +43-1-8178292-82 :
> : Schoenbrunner Str. 244, A-1120 Vienna/Europe   http://www.linbit.com :
> __
> please use the "List-Reply" function of your email client.
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user
>



More information about the drbd-user mailing list