[Lustre-discuss] Performance parameters

[Enrico Morelli]

On Fri, 06 Jun 2008 11:24:28 -0400
"Brian J. Murrell" <Brian.Murrell at Sun.COM> wrote:

> On Fri, 2008-06-06 at 17:06 +0200, Enrico Morelli wrote:
> > 
> > On lustre:
> >  time dd if=/dev/zero of=test.txt bs=1M count=1024
> > 1024+0 records in
> > 1024+0 records out
> > 
> > real    0m21.260s
> 
> So, about 48MiB/s, yes?  What does your storage backend look like?

The server is connected to an MSA60 with 7x500GB SATA HDD in RAID 6.

> 
> > user    0m0.000s
> > sys     0m1.600s
> > 
> > On NFS:
> > time dd if=/dev/zero of=test.txt bs=1M count=1024   
> > 1024+0 records in
> > 1024+0 records out
> > 
> > real    0m2.561s
> 
> 399MiB/s.  Do you believe this?  Does it correlate with the storage
> backend on the NFS server and the network interconnect between your
> NFS client and NFS server?

Sorry, sorry, sorry, I'm very tired. I connected directly to the NFS
server :-(((( On a client machine the time is more than 1 minutes.

The problem is that a lot of people told me that 'ls' required a lot of
time, a 'cp' required a lot of time, all operations on lustre
filesystem are very slow. The people that works on lustre has a lot of
files to manage, so testing his directories I found that an 'ls' require
a lot of time and the same for 'cp' and 'rm' operations.

The dd was not a better test to do. Sorry again.

-- 
-------------------------------------------------------------------
       (o_
(o_    //\  Coltivate Linux che tanto Windows si pianta da solo.
(/)_   V_/_
+------------------------------------------------------------------+
|     ENRICO MORELLI         |  email: morelli at CERM.UNIFI.IT       |
| *     *       *       *    |  phone: +39 055 4574269             |
|  University of Florence    |  fax  : +39 055 4574253             |
|  CERM - via Sacconi, 6 -  50019 Sesto Fiorentino (FI) - ITALY    |
+------------------------------------------------------------------+