Date: Thu, 01 Jul 1999 17:01:58 -0700 From: David Greenman <dg@root.com> To: Zhihui Zhang <zzhang@cs.binghamton.edu> Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: reason for slow user-user memory copy Message-ID: <199907020001.RAA07819@implode.root.com> In-Reply-To: Your message of "Thu, 01 Jul 1999 19:36:10 EDT." <Pine.GSO.3.96.990701192815.3735C-100000@sol.cs.binghamton.edu>
next in thread | previous in thread | raw e-mail | index | archive | help
>> If the mapping is being done via a device mapping, then the region will >> be marked non-cacheable. > >I remember that he said he created a character device /dev/tulip to >represent the network card. Actually, his work borrowed a lot from the >Cornell U-Net project (now the basis of VIA?). Can we change the >corresponding page table (directory) entries to be cacheable as needed? You'd have to modify the kernel - specifically pmap_mapdev(). Note that the above behavior is only true for older versions of FreeBSD (pre-2.2). If you're having this problem within a newer version of FreeBSD, then it's probably something else causing it. -DG David Greenman Co-founder/Principal Architect, The FreeBSD Project - http://www.freebsd.org Creator of high-performance Internet servers - http://www.terasolutions.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199907020001.RAA07819>