[Ocfs2-users] ocfs2 vs ext3?

[Sunil Mushran]

Andrew (Anything) wrote:
> Ive been testing using bonnie++ -n 50:1024:0:10 -s 0. Is this a bad way to
> test?
> Some raw results follow later in case you want them.
>
> Obviously ocfs2 should be slower than ext3.
> But I guess I expected a single node ocfs node to be only doing internal
> stuff with kernel and dlm at really fast cpu speeds, and its only bottleneck
> to be writing to the disk. For it to be so slow it must be doing heaps of
> disk stuff instead?
>
> Had tried a few dd tests however oflag=direct seems to cause an instant
> kernel panic, I don't know if I am to trust dd's results without directio.
>
> Andy..
>
>
> ext3, noatime,
> bonnie++ -d /mnt/temp/ -n 50:1024:0:10 -s 0
> Version 1.03e       ------Sequential Create------ --------Random
> Create--------
> wombat              -Create-- --Read--- -Delete-- -Create-- --Read---
> -Delete--
> files:max            /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec
> %CP
>        50:1024:0/10 10838  43 +++++ +++ 20386  50  7147  28 +++++ +++ 17248
> 44
>
>
> ocfs2, -T mail max-features, noatime,data=writeback,
> bonnie++ -d /mnt/temp/ -n 50:1024:0:10 -s 0
> Version 1.03e       ------Sequential Create------ --------Random
> Create--------
> wombat              -Create-- --Read--- -Delete-- -Create-- --Read---
> -Delete--
> files:max            /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec
> %CP
>        50:1024:0/10  1429  53 10849  32  1224   8  1354  51   205   2   292
> 4
>
> I ran both a few times just in case.

Yes, it is doing heaps more disk io compared to ext3 simply due to the fact
the ext3's inode is 128 bytes whereas ocfs2's is 1 block. So choosing a
smaller block size will improve create performance. However, that is not
recommended because smaller block sizes will negatively affect the r/w
performance.

Have you tried running bonnie on multiple nodes concurrently? The create
performance will scale up to the limit of your io subsystem.