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From: Luigi Rizzo <luigi@labinfo.iet.unipi.it>
Message-Id: <199505190530.HAA09463@labinfo.iet.unipi.it>
Subject: Re: ram-speed (was Re: Adaptec 2940?)
To: asami@CS.Berkeley.EDU (Satoshi Asami | =?ISO-2022-JP?B?GyRCQHUbKEI=?= =?ISO-2022-JP?B?GyRCOCsbKEIgGyRCOC0bKEI=?=)
Date: Fri, 19 May 1995 07:30:40 +0200 (MET DST)
Cc: adhir@iagi.net, aledm@pavilion.co.uk, hackers@FreeBSD.org
In-Reply-To: <199505190411.VAA09502@silvia.HIP.Berkeley.EDU> from "Satoshi Asami | =?ISO-2022-JP?B?GyRCQHUbKEI=?= =?ISO-2022-JP?B?GyRCOCsbKEIgGyRCOC0bKEI=?=" at May 18, 95 09:11:09 pm
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>     49005fb0   0.418 uS/op 2.39e+06 op/S  9.121 Mb/S
>     8938c0df   0.170 uS/op 5.89e+06 op/S 22.462 Mb/S

What does this test measure ? Is it just reads and writes, or something
more ? It looks kind of strange to me that reads
take so long (418nS) to complete, even if you have a cache miss every
time.

BTW, on a couple of systems here, I see values such as 4.810/24.774
(the first looks quite low, I guess I have to play with the setup of
the board).

Also, the test takes quite long to complete. I noticed that if I reduce
the number of loops the results don't change significantly.

	Luigi
====================================================================
Luigi Rizzo                     Dip. di Ingegneria dell'Informazione
email: luigi@iet.unipi.it       Universita' di Pisa
tel: +39-50-568533              via Diotisalvi 2, 56126 PISA (Italy)
fax: +39-50-568522
====================================================================