From: Jim Schutt Subject: Re: XPRTRDMA max payload? Date: Thu, 4 Sep 2008 15:39:37 +0000 (UTC) Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: linux-nfs@vger.kernel.org Return-path: Received: from main.gmane.org ([80.91.229.2]:50067 "EHLO ciao.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751436AbYIDPpJ (ORCPT ); Thu, 4 Sep 2008 11:45:09 -0400 Received: from root by ciao.gmane.org with local (Exim 4.43) id 1KbH14-0005v5-To for linux-nfs@vger.kernel.org; Thu, 04 Sep 2008 15:45:03 +0000 Received: from sahp4062.sandia.gov ([134.253.26.11]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 04 Sep 2008 15:45:02 +0000 Received: from jaschut by sahp4062.sandia.gov with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 04 Sep 2008 15:45:02 +0000 Sender: linux-nfs-owner@vger.kernel.org List-ID: Scott Atchley writes: > > Hi all, > > I thought that the max payload for XPRTRDMA would be 1 MB. It seems to > be set on the client to 23 KB (RPCRDMA_MAX_DATA_SEGS * PAGE_SIZE). The > server, on the other hand, sets it to 1 MB (RPCSVC_MAXPAYLOAD_TCP). > > If I try to mount with rdma with: > > # mount.nfs host:/exports /mnt/test -o > rdma,port=2050,rsize=1048576,wsize=1048576 > > It ignores the size parameters and /proc/mounts shows it is 32 KB. > > Is there a way to increase it at loadtime or runtime or do I need to > change RPCRDMA_MAX_DATA_SEGS and recompile? That's the only way I was able to find to do it. You'll want this patch also: http://marc.info/?l=linux-nfs&m=121936891515202&w=2 There are some things on the stack dimensioned by RPCRDMA_MAX_DATA_SEGS. I've not encountered any problems using 16 for RPCRDMA_MAX_DATA_SEGS, but I've not tried anything bigger. -- Jim > > Thanks, > > Scott > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@... > More majordomo info at http://vger.kernel.org/majordomo-info.html > >