On Thu, 2013-09-05 at 16:36 -0500, Quentin Barnes wrote: > On Thu, Sep 05, 2013 at 08:02:01PM +0000, Myklebust, Trond wrote: > > On Thu, 2013-09-05 at 14:11 -0500, Quentin Barnes wrote: > > > On Thu, Sep 05, 2013 at 12:03:03PM -0500, Malahal Naineni wrote: > > > > Neil Brown posted a patch couple days ago for this! > > > > > > > > http://thread.gmane.org/gmane.linux.nfs/58473 > > > > > > I tried Neil's patch on a v3.11 kernel. The rebuilt kernel still > > > exhibited the same 1000s of WRITEs/sec problem. > > > > > > Any other ideas? > > > > Yes. Please try the attached patch. > > Great! That did the trick! > > Do you feel this patch could be worthy of pushing it upstream in its > current state or was it just to verify a theory? > > > In comparing the nfs_flush_incompatible() implementations between > RHEL5 and v3.11 (without your patch), the guts of the algorithm seem > more or less logically equivalent to me on whether or not to flush > the page. Also, when and where nfs_flush_incompatible() is invoked > seems the same. Would you provide a very brief pointer to clue me > in as to why this problem didn't also manifest circa 2.6.18 days? There was no nfs_vm_page_mkwrite() to handle page faults in the 2.6.18 days, and so the risk was that your mmapped writes could end up being sent with the wrong credentials. -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@xxxxxxxxxx www.netapp.com ��.n��������+%������w��{.n�����{��w��� jg��� �����ݢj����G���� ���j:+v���w�m������w�������h�����٥
