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Date: Thu, 04 Feb 2010 10:21:13 -0800 (PST)
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To: opurdila@ixiacom.com
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Subject: Re: [RFC Patch] net: reserve ports for applications using fixed
 port numbers
From: David Miller <davem@davemloft.net>
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From: Octavian Purdila <opurdila@ixiacom.com>
Date: Thu, 4 Feb 2010 20:15:51 +0200

> int inet_is_reserved_local_port(int port)
> {
> 	if (test_bit(port, reserved_ports))
> 		return 1;
> 	return 0;
> }
> 
> In theory it might be slower because of the reserved_ports bitmap will have a 
> larger memory footprint than just a min/max, especially with random port 
> allocation. But is this an issue in practice?

No need to speculate, some simple benchmarks would confirm or deny
this.