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Date: Thu, 12 Jun 1997 10:49:39 +0300 (EEST)
From: Narvi <narvi@haldjas.folklore.ee>
To: hackers@freebsd.org
Subject: PQ_LARGECACHE and page colouring
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	Hello!

There is a thing called page colouring in the FreeBSD kernel.

Using a 512K cache on my oldish ASUS P/I P55TP4XE, and a P133, I get using 

dd if=/dev/zero of=/dev/null bs=1m count=2000

2097152000 bytes transferred in 18.668431 secs (112336811 bytes/sec)

With a stock 2.2-RELEASE kernel and

2097152000 bytes transferred in 18.068088 secs (116069392 bytes/sec)

if I add options PQ_LARGECACHE to the kernel config file.

I know the change (3.7MB/s -> ~3%) is not that much, but if you can get it
by just adding one line to the config file, it might be worth it. 

Now the problem is - PQ_XXXXCACHE is not documented anywhere, not even in
the LINT. Perhaps we should change this?

	Sander