Re: Shared Memory Sizing - Mailing list pgsql-general

From Curt Sampson
Subject Re: Shared Memory Sizing
Date
Msg-id Pine.NEB.4.43.0206281311030.6613-100000@angelic.cynic.net
Whole thread Raw
In response to Re: Shared Memory Sizing  (Andrew Sullivan <andrew@libertyrms.info>)
Responses Re: Shared Memory Sizing  (Andrew Sullivan <andrew@libertyrms.info>)
List pgsql-general
On Thu, 27 Jun 2002, Andrew Sullivan wrote:

> For what it's worth, truss on Solaris 7 indicates that copying from
> OS buffer costs a few milliseconds (between 2 and 8 in our tests,
> depending on load), at least in our tests.

Ouch! Are you sure you mean MILLIseconds, rather than MICROSECONDS?

    8K in 2 ms. = 4 MB/sec.
    8K in 8 usec. = 976 MB/sec.

The latter would be a much more reasonable figure for memory bandwidth...

cjs
--
Curt Sampson  <cjs@cynic.net>   +81 90 7737 2974   http://www.netbsd.org
    Don't you know, in this new Dark Age, we're all light.  --XTC




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