Re: [PATCH v3 3/3] NFSD: Add support for encoding multiple segments

J. Bruce Fields
2015-03-26T15:38:51Z

On Thu, Mar 26, 2015 at 11:32:25AM -0400, Trond Myklebust wrote:
> On Thu, Mar 26, 2015 at 11:21 AM, Anna Schumaker
> <Anna.Schumaker@netapp.com> wrote:
> > Here are my updated numbers! I tested with files 5G in size: one 100% data, one 100% hole, and one alternating between hole and data every 4K. I collected data for both v4.1 and v4.2 with and without the READ_PLUS patches:
> >
> > ##########################
> > # #
> > # Without READ_PLUS #
> > # #
> > ##########################
> >
> >
> > NFS v4.1:
> > Trial
> > |---------|---------|---------|---------|---------|---------|---------|
> > | | 1 | 2 | 3 | 4 | 5 | Average |
> > |---------|---------|---------|---------|---------|---------|---------|
> > | Data | 8.723s | 7.243s | 8.252s | 6.997s | 6.980s | 7.639s |
> > | Hole | 5.271s | 5.224s | 5.060s | 4.897s | 5.321s | 5.155s |
> > | Mixed | 8.050s | 10.057s | 7.919s | 8.060s | 9.557s | 8.729s |
> > |---------|---------|---------|---------|---------|---------|---------|
> >
> >
> >
> >
> > NFS v4.2:
> > Trial
> > |---------|---------|---------|---------|---------|---------|---------|
> > | | 1 | 2 | 3 | 4 | 5 | Average |
> > |---------|---------|---------|---------|---------|---------|---------|
> > | Data | 6.707s | 7.070s | 6.722s | 6.761s | 6.810s | 6.814s |
> > | Hole | 5.152s | 5.149s | 5.213s | 5.206s | 5.312s | 5.206s |
> > | Mixed | 7.979s | 7.985s | 8.177s | 7.772s | 8.280s | 8.039s |
> > |---------|---------|---------|---------|---------|---------|---------|
> >
> >
> >
> >
> >
> > #######################
> > # #
> > # With READ_PLUS #
> > # #
> > #######################
> >
> >
> > NFS v4.1:
> > Trial
> > |---------|---------|---------|---------|---------|---------|---------|
> > | | 1 | 2 | 3 | 4 | 5 | Average |
> > |---------|---------|---------|---------|---------|---------|---------|
> > | Data | 9.082s | 7.008s | 7.116s | 6.771s | 7.902s | 7.576s |
> > | Hole | 5.333s | 5.358s | 5.380s | 5.161s | 5.282s | 5.303s |
> > | Mixed | 8.189s | 8.308s | 9.540s | 7.937s | 8.420s | 8.479s |
> > |---------|---------|---------|---------|---------|---------|---------|
> >
> >
> >
> >
> > NFS v4.2:
> > Trial
> > |---------|---------|---------|---------|---------|---------|---------|
> > | | 1 | 2 | 3 | 4 | 5 | Average |
> > |---------|---------|---------|---------|---------|---------|---------|
> > | Data | 7.033s | 6.829s | 7.025s | 6.873s | 7.134s | 6.979s |
> > | Hole | 1.794s | 1.800s | 1.905s | 1.811s | 1.725s | 1.807s |
> > | Mixed | 7.590s | 8.777s | 9.423s | 10.366s | 8.024s | 8.836s |
> > |---------|---------|---------|---------|---------|---------|---------|
> >
>
> So there is a clear win in the 100% hole case here, but otherwise the
> statistical fluctuations are dominating the numbers. Can you get us a
> little more stats and then perhaps run the results through nfsometer?

Also, could you describe the setup (are these still kvm's), and how
you're clearing the cache between runs?

--b.