Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:47504 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750897AbaELBGH (ORCPT ); Sun, 11 May 2014 21:06:07 -0400 Date: Mon, 12 May 2014 11:05:57 +1000 From: NeilBrown To: "J. Bruce Fields" Cc: Jan Kara , Jeff Layton , Trond Myklebust , Dave Chinner , Mel Gorman , Andrew Morton , linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/5] nfsd: Only set PF_LESS_THROTTLE when really needed. Message-ID: <20140512110557.67f2028e@notabene.brown> In-Reply-To: <20140506205418.GQ18281@fieldses.org> References: <20140423022441.4725.89693.stgit@notabene.brown> <20140423024058.4725.38098.stgit@notabene.brown> <20140506205418.GQ18281@fieldses.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/_V4z.i1JTXug8PX71jSjKud"; protocol="application/pgp-signature" Sender: linux-nfs-owner@vger.kernel.org List-ID: --Sig_/_V4z.i1JTXug8PX71jSjKud Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Tue, 6 May 2014 16:54:18 -0400 "J. Bruce Fields" wrote: > On Wed, Apr 23, 2014 at 12:40:58PM +1000, NeilBrown wrote: > > PF_LESS_THROTTLE has a very specific use case: to avoid deadlocks > > and live-locks while writing to the page cache in a loop-back > > NFS mount situation. > >=20 > > It therefore makes sense to *only* set PF_LESS_THROTTLE in this > > situation. > > We now know when a request came from the local-host so it could be a > > loop-back mount. We already know when we are handling write requests, > > and when we are doing anything else. > >=20 > > So combine those two to allow nfsd to still be throttled (like any > > other process) in every situation except when it is known to be > > problematic. >=20 > Looks simple enough, ACK.--b. >=20 Thanks. I'll resend the bits need for just this. The NFS side need to wait for wait_on_bit improvements which seem to be on a slow path at the moment. Thanks, NeilBrown --Sig_/_V4z.i1JTXug8PX71jSjKud Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBU3AedTnsnt1WYoG5AQLtVQ//ca3F1FKgZ1bg4vldC4AC0h6yeS6OW2kb 71BlpBNF69xL/yY56j2JTOtxf/SDJxf/UGPjChxpaIpcf/npZPPT4mfUL+7AruNm pBbLtenwSnU0GRvCuDednJwt33mZ33minfW7Gzhsc1Uj2s0Rd0yaUnio7DTNBpgI KuIgcN/LKuEz+u+ItEpcQ3fCE0uOS8/W9prYPcyZvHH+DrwyLwpHFz2CV2WNsdRZ zpwRb8aQNXTnJKuTDgUieZOIB9/eSK5+uznhzd7VwcRhdAU4edduI26gVNxjkgZb zDggyM55TyNxtDK/hSTWpmHYybI9dznUDNkQs3FVzGyw/dGKxLHxY2X2FkNLleUr yqpqMla309OOm4/gAL/vCaLUTVtyirOqJbyn6Qtv3qFccG2HnRp4qvk+YLMIZuyF 5cxg56+3KXGRvES08KJchzk+RP9lpShyhAuyUJEZV2DmyvAFDUbMrKakkVEyeUnj F69+uEccPX3qZ3E0Z4Yo5ryaZGcndeevVYgFDTQn0GvKleLNK3oclVtIM+d68Duq jzeh/Ejj0j2TGgzPs0clQ1EDLCC81ka/GHEeBkVLaejV0Yd9b/MovwxFf4UZQbkJ 8AqoHzmWrj4k3qe7uHwXRzi4AlzFBbt3/nqXy3ROkNJCdbMVblzJxsihv7bGX+tf 29nSQoHbuT4= =epl8 -----END PGP SIGNATURE----- --Sig_/_V4z.i1JTXug8PX71jSjKud--