atom feed16 messages in org.freebsd.freebsd-stableRe: Dump takes ages on SCSI. (several...
FromSent OnAttachments
David GilbertJul 2, 2000 1:24 pm 
Kent StewartJul 2, 2000 2:53 pm 
David GilbertJul 2, 2000 5:42 pm 
Kent StewartJul 2, 2000 6:50 pm 
Chad R. LarsonJul 2, 2000 8:44 pm 
David GilbertJul 2, 2000 9:25 pm 
Kenneth D. MerryJul 2, 2000 10:55 pm 
David MaloneJul 3, 2000 12:01 am 
kostikJul 3, 2000 1:35 am 
Gerhard SittigJul 3, 2000 10:38 am 
Mike SmithJul 3, 2000 6:57 pm 
Mike SmithJul 4, 2000 4:08 am 
Mike SmithJul 4, 2000 5:22 am 
Gerhard SittigJul 4, 2000 10:16 am 
Mike SmithJul 6, 2000 2:36 am 
Don LewisJul 14, 2000 1:36 am 
Subject:Re: Dump takes ages on SCSI. (several times faster on IDE)
From:Mike Smith (msm@freebsd.org)
Date:Jul 4, 2000 4:08:25 am
List:org.freebsd.freebsd-stable

When the da(4) driver does a dump, it uses the CAM transport layer's polled completion/action facility, xpt_polled_action().

It looks like there is a substantial delay (1ms) in that routine between poll intervals.

That would still allow 4MB/sec (1 page per I/O) - I think there's more to it than just that.

-- ... every activity meets with opposition, everyone who acts has his rivals and unfortunately opponents also. But not because people want to be opponents, rather because the taks and relationships force people to take different points of view. [Dr. Fritz Todt]

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