Messages in this thread | | | From | "Andrew Scott" <> | Date | Wed, 13 Sep 2000 15:02:59 -0400 | Subject | Re: (reiserfs) Re: More on 2.2.18pre2aa2 (summary of elevator ideas) |
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On 12 Sep 2000, at 18:08, Ed Tomlinson wrote:
> Hi, > > I made the comment because I remember back when the discussion was current > on linux kernel. I thought Jeff Merkey's, message was to the point. Para- > phrasing from memory, it was something to the effect that novell had > tried many elevators. All had problems with some loads. The best they > had found was the 'close the door' idea. I do not remember if the door > was based on requests or time. Another point to remember is that the > netware people came up with a what they considered a good solution.
I believe that the Netware elevator is based on outstanding requests. This is a tunable parameter which may be increased for fast disk subsystems.
I think that you could consider the number of requests to be loosely related to time. That is, the time to service 50 requests should be fairly predictable for a given disk/controller. I don't think you need to time stamp every request to get good results.
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