Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:49387 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751190AbaGHOr6 (ORCPT ); Tue, 8 Jul 2014 10:47:58 -0400 Date: Tue, 8 Jul 2014 10:47:57 -0400 To: Cedric Blancher Cc: Linux NFS Mailing List Subject: Re: NFSv4 delegations criteria? Fwd: Tuning Linux NFSv4 for high latency connections? Message-ID: <20140708144757.GA23212@fieldses.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, Jul 07, 2014 at 06:24:41PM +0200, Cedric Blancher wrote: > Anyone? > > Ced > > On 23 April 2014 23:03, Cedric Blancher wrote: > > What are the criteria for grating a file delegation in NFSv4? They're generally implementation-specific. > > Are file > > delegations retained even if a process closes a file and the next > > process in the chain opens it again (e.g. in a shell script)? Yes, they can be. > > > > Ced > > > > PS: Who again grants NFSv4 delegations? Server or client? The server. > > Do > > delegations work when data are appended at the end of a file? The holder of a write delegation can append, yes. The rfc's (3530 and 5661) have some more details. I suspect the Solaris server supports write delegations. The Linux server doesn't. Hard to tell the reason for the performance difference you describe, though, you'd probably need to gather some statistics. --b. > > > > ---------- Forwarded message ---------- > > From: Cedric Blancher > > Date: 23 April 2014 20:01 > > Subject: Tuning Linux NFSv4 for high latency connections? > > To: Linux NFS Mailing List > > > > > > Are there any options to improve the Linux NFSv4 performance over a > > high latency connection? > > > > We currently use Solaris/Illumos as NFSv4 server and client over a > > cross continental Internet connection. Latency is terrible (~220ms) > > but the counter this by running work in parallel so the latency is > > mostly mitigated. > > > > We now wish to migrate (short: Away from Oracle because support is > > basically unbearable) to Linux (tested SuSE 13.1 and current Fedora) > > and build times are 17 times (!!!) SLOWER than on Solaris/Illumos. > > > > Are there any tunables besides actimeo=300? > > > > Ced > > -- > > Cedric Blancher > > Institute Pasteur > > > > > > -- > > Cedric Blancher > > Institute Pasteur > > > > -- > Cedric Blancher > Institute Pasteur > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html