From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.2 required=5.0 tests=MAILING_LIST_MULTI, NICE_REPLY_A autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 18002 invoked from network); 21 Oct 2020 13:23:25 -0000 Received: from alyss.skarnet.org (95.142.172.232) by inbox.vuxu.org with ESMTPUTF8; 21 Oct 2020 13:23:25 -0000 Received: (qmail 29363 invoked by uid 89); 21 Oct 2020 13:23:50 -0000 Mailing-List: contact supervision-help@list.skarnet.org; run by ezmlm Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Received: (qmail 29356 invoked from network); 21 Oct 2020 13:23:50 -0000 Subject: Re: Dependencies in S6 To: supervision@list.skarnet.org References: From: Crest Message-ID: Date: Wed, 21 Oct 2020 15:23:21 +0200 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.12.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US On 21.10.20 12:10, Amaresh Kotekal wrote: > Hi Team, > > I have some doubt on dependencies file in S6. > > Secnario 1: > 1. A & B are one shot services in a s6-rc bundle. Service B is dependent on > A. ( added in dependency file). > 2. I think Service B will start after the completion of service A ( A then > B, in serial manner ) is it correct ? or > 3. Service B will start immediately after the service A as started (in a > parallel manner) ? > > Secnario 2: > 1. A is one shot service and B is a long run service. Service B is > dependent on Service A. > 2. Service B will start, once th service A as completed (in serial manner) > ? or > 3. Service B will start immediately after the service A as started (in a > parallel manner) ? > > Secnario 3: > 1. A is a long run service and B is a one shot service. Service B is > dependent on Service A. > 2. Service B will start immediately after the service A as started (in a > parallel manner) ? > 3. Do I need to use notification mechanism if I want to start service B > after A service as reached particular point in execution > > Secnario 4: > 1. A & B both are long run services. Service B is dependent on Service A. > 2. Service B will start immediately after the service A as started (in a > parallel manner) ? > > If one shot service are dependent on other one shot services. They will be > started in serial manner one after the other ? The s6-rc service manager is always concurrent while respecting dependencies. It starts all services as soon as their requirements are satisfied. Having a single service depend on a single other service is just a special case of the more general dependency resolution s6-rc does.