From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aurelien Degremont Date: Thu, 21 Feb 2008 16:26:07 +0100 Subject: [Lustre-devel] Lustre HSM HLD draft In-Reply-To: <47AAE307.9040305@cea.fr> References: <47AAE307.9040305@cea.fr> Message-ID: <47BD980F.50201@cea.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org Hello I've got several wondering about some specific point in HSM implementation and I would like your opinion about them. Coordinator: This element will manage migration externally (HSM) and internally of Lustre (space balancing?). Is the current API acceptable (specific calls for external migration, and other ones for internal migration)? The best way could have been to have generic call for migration, but we must also have generic objects to describe the migration sources and destinations and those are not simples. We finally conclude with the API presented in the HLD document. Tell me if this is *really* a bad idea or if only adjustments are needed. We presented two modes of migration, explicit and implicit migrations. The first one result of an administrative request, the second one was triggered automatically (cache miss by example). Is that ok? (See the doc for all details). Agent: It seems, to support Lustre internal migration, you have planned to implement specific Agents which will reside on OST. HSM will need specific agent on clients. Do those two kinds of agent are acceptable ? The current API only describe HSM-based agent. Maybe we should think of a generic agent framework and add specialized implementations for ost,hsm,etc ? -- Aurelien Degremont CEA