From owner-freebsd-current Sat Apr 20 21:32:11 1996 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id VAA22379 for current-outgoing; Sat, 20 Apr 1996 21:32:11 -0700 (PDT) Received: from localhost.cdrom.com (localhost.cdrom.com [127.0.0.1]) by freefall.freebsd.org (8.7.3/8.7.3) with SMTP id VAA22374 for ; Sat, 20 Apr 1996 21:32:10 -0700 (PDT) Message-Id: <199604210432.VAA22374@freefall.freebsd.org> X-Authentication-Warning: freefall.freebsd.org: Host localhost.cdrom.com [127.0.0.1] didn't use HELO protocol To: current Subject: Aic7xxx driver update in current Date: Sat, 20 Apr 1996 21:32:10 -0700 From: "Justin T. Gibbs" Sender: owner-current@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk For those of you who don't watch the commit mailing list, I've just put into current my changes to allow SCB paging on the aic7xxx cards. What does this mean for you? It should mean better throughput in your server class machines. SCB paging allows up to 255 concurrent commands on the adapters that support it which means more tagged commands active per device and better I/O scheduling to reduce seek times. Because the code is new and has only been tested by two people so far, it is not enabled by default. You must add the option "AHC_SCBPAGING_ENABLE" to your kernel config file. The default behavior of the driver is to use 4 tags per device without SCB paging and 8 with. This may change as I get more information from people using the driver and do more benchmarks. Tagged queueing is no longer an option (its been tested for 1 year now) and the QUEUE_FULL_SUPPORTED stuff has gone away too. Please test out the new driver and report any problems back to me. I intend to bring this driver into -stable soon (as it fixes some other bugs too), but I want to wait for more people to test it in -current first. Thanks! -- Justin T. Gibbs =========================================== FreeBSD: Turning PCs into workstations ===========================================