From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: Re: a simple and scalable pNFS block layout server Date: Tue, 6 Jan 2015 10:37:08 -0800 Message-ID: <20150106103708.70a06aba@synchrony.poochiereds.net> References: <1420561721-9150-1-git-send-email-hch@lst.de> <20150106173222.GF12067@fieldses.org> <20150106175611.GA16413@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "J. Bruce Fields" , linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, xfs-VZNHf3L845pBDgjK7y7TUQ@public.gmane.org, Weston Andros Adamson To: Christoph Hellwig Return-path: In-Reply-To: <20150106175611.GA16413-jcswGhMUV9g@public.gmane.org> Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-fsdevel.vger.kernel.org On Tue, 6 Jan 2015 18:56:11 +0100 Christoph Hellwig wrote: > On Tue, Jan 06, 2015 at 12:32:22PM -0500, J. Bruce Fields wrote: > > - do we have evidence that this is useful in its current form? >=20 > What is your threshold for usefulness? It passes xfstests fine, and > shows linear scalability with multiple clients that each have 10GB > links.=20 >=20 > > - any advice on testing? Is there was some simple virtual setup > > that would allow any loser with no special hardware (e.g., me) > > to check whether they've broken the block server? >=20 > Run two kvm VMs that share the same disk. Create an XFS filesystem > on the MDS, and export it. If the client has blkmapd running (on Deb= ian > it needs to be started manually) it will use pNFS for accessing the > filesystem. Verify that using the per-operation counters in > /proc/self/mounstats. Repeat with additional clients as nessecary. >=20 > Alternatively set up a simple iSCSI target using tgt or lio and > connect to it from multiple clients. >=20 > > - any debugging advice? E.g., have you checked if current > > wireshark can handle the MDS traffic? >=20 > The wireshare version I've used decoded the generic pNFS operations > fine, but just dumps the layout specifics as hex data. >=20 > Enable the trace points added in this series, they track all stateid > interactions in the server. Addit=D1=96onally the pnfs debug printks= on > client and server dump a lot of information. The wireshark decoder really only handles files layouts right now. Dros has some patches to add flexfiles support too (once the spec is a bit more finalized) and at that point it shouldn't be too hard to fix it to handle block layout as well. --=20 Jeff Layton -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html