On Thu, Mar 26, 2015 at 12:11 PM, Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> wrote: > On 03/26/2015 12:06 PM, Trond Myklebust wrote: >> On Thu, Mar 26, 2015 at 11:47 AM, Anna Schumaker >> <Anna.Schumaker@xxxxxxxxxx> wrote: >>> On 03/26/2015 11:38 AM, J. Bruce Fields wrote: >>>> 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@xxxxxxxxxx> 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? >>> >>> These are still KVMs and my server is exporting an xfs filesystem. I clear caches by running "echo 3 > /proc/sys/vm/drop_caches" on the server before every read, and I remount my client after reading each set of three files once. >> >> I agree that you have to use the 'drop_caches' interface on the >> server, but why not just use O_DIRECT on the clients? > > I've been reading by using cat from my test shell script: `time cat /nfs/file > /dev/null`. I can write something to read files with O_DIRECT if that would be more useful! > 'dd' can do that for you if the appropriate incantations are performed. -- Trond Myklebust Linux NFS client maintainer, PrimaryData trond.myklebust@xxxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
