Date: Wed, 03 Feb 2010 16:00:27 +0200 From: Alexander Motin <mav@FreeBSD.org> To: "James R. Van Artsdalen" <james-freebsd-current@jrv.org> Cc: FreeBSD-Current <freebsd-current@freebsd.org> Subject: Re: Pack of CAM improvements Message-ID: <4B69817B.8090706@FreeBSD.org> In-Reply-To: <4B570B4C.9000203@jrv.org> References: <4B55D9D4.1000008@FreeBSD.org> <823F6536-32A7-4BC6-9C6A-C84865A38458@samsco.org> <4B570B4C.9000203@jrv.org>
next in thread | previous in thread | raw e-mail | index | archive | help
James R. Van Artsdalen wrote: > At some point I hope to add support for staggered spin-ups, perhaps a > loader.conf setting for people with more than 20-30 disks. At the > 100-120 disk level it seems unlikely that any reasonable fixed delay > would be reasonable. I've just added Power Up In Stand-by (PUIS) feature support into CAM ATA in HEAD. It is one of the ways to implement staggered spin-up for ATA devices. Now CAM will spin-up no more then 4 of such devices at a time. Another way, based on SATA hard-reset sequence, is more complicated (especially when port multipliers used) and not supported yet. -- Alexander Motin
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4B69817B.8090706>