From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AE51C43334 for ; Thu, 9 Jun 2022 15:04:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241803AbiFIPEF (ORCPT ); Thu, 9 Jun 2022 11:04:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344118AbiFIPEF (ORCPT ); Thu, 9 Jun 2022 11:04:05 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CD57B1912C5 for ; Thu, 9 Jun 2022 08:04:03 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 5C6BC21D3F; Thu, 9 Jun 2022 15:04:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1654787042; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=hsyK7MiMPwm5+uvoSQLzwg8ZL20pGHFEMUQJNCvxKIQ=; b=QBcIMEvzVpcmyQZDYPknXDsUYrDMWo2skQ2THKJb5q7DKrNz7Q8K/4W4Y/K42nvtWgWZhX Aft+PT+/e+zCcIU6+oz8FGVP2kHPwIswr3lTW1GowMKjV9GIUtiY2+9bB737bMBgsuApH7 nSeHeqT93BhZLV8BqvEfz44dfD3y8Oc= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1654787042; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=hsyK7MiMPwm5+uvoSQLzwg8ZL20pGHFEMUQJNCvxKIQ=; b=byP/o0uP0mVQwnWzz5nmz9uhfTSHLfCr116M6DcVdTJu3DbBVhdLTZ78869d72I+I6thGM dnkFjYm5EiaIspBg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id C779013A8C; Thu, 9 Jun 2022 15:04:01 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id MfQ+IeELomIfAgAAMHmgww (envelope-from ); Thu, 09 Jun 2022 15:04:01 +0000 Date: Thu, 9 Jun 2022 12:03:59 -0300 From: Enzo Matsumiya To: Tom Talpey Cc: linux-cifs@vger.kernel.org, smfrench@gmail.com, pc@cjr.nz, ronniesahlberg@gmail.com, nspmangalore@gmail.com Subject: Re: [PATCH 0/2] Introduce dns_interval procfs setting Message-ID: <20220609150359.5uioqx4eccfodo6e@cyberdelia> References: <20220608215444.1216-1-ematsumiya@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org On 06/09, Tom Talpey wrote: >On 6/8/2022 5:54 PM, Enzo Matsumiya wrote: >>Hi, >> >>These 2 patches are a simple way to fix the DNS issue that >>currently exists in cifs, where the upcall to key.dns_resolver will >>always return 0 for the record TTL, hence, making the resolve worker >>always use the default value SMB_DNS_RESOLVE_INTERVAL_DEFAULT >>(currently 600 seconds). >> >>This also makes the new setting `dns_interval' user-configurable via >>procfs (/proc/fs/cifs/dns_interval). >> >>One disadvantage here is that the interval is applied to all hosts >>resolution. This is still how it works today, because we're always using >>the default value anyway, but should someday this be fixed, then we can >>go back to rely on the keys infrastructure to cache each hostname with >>its own separate TTL. > >Curious, why did you choose a procfs global approach? Wouldn't it be >more appropriate to make this a mount option, so it would be applied >selectively per-server? I tried to stick to the current behaviour, while also fixing the issue of getting a TTL=0 from key.dns_resolver upcall. A mount option looks indeed better initially, and that was also my initial approach to this. But in a, e.g. multi-domain forest, with multiple DFS targets, the per-mount setting starts to look irrelevant again as well. So I took the "per-client" approach instead. Cheers, Enzo