Date: Wed, 13 Sep 1995 12:59:47 +1000 From: Bruce Evans <bde@zeta.org.au> To: hackers@FreeBSD.org Subject: Re: higher density diskettes Message-ID: <199509130259.MAA19273@godzilla.zeta.org.au>
next in thread | raw e-mail | index | archive | help
>> ... The FreeBSD driver uses a head >> settle delay of hz/16 ticks, i.e., between 50 and 60 ms. This is much >> longer than necessary. I think the spec is 15 msec. >The spec suffers from a lack of reality. We've once had hz/32, and >got (too) many problem reports. That's why the more conservative >value has been used. Perhaps the extra delay is compensating for a bug elsewhere. >I know that the existing driver is not at the end of optimization, but >i'm not sure whether a potential gain of 25 % or less in speed would >be worth the effort. People usually only recognize speed changes by a >factor of 2 or more. 25% was for the simple sequential case that the existing driver handles best. Bruce
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199509130259.MAA19273>