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From: Rusty Russell <rusty@rustcorp.com.au>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: furwocks: Fast Userspace Read/Write Locks
Date: Fri, 08 Mar 2002 18:09:18 +1100	[thread overview]
Message-ID: <E16jEVC-0006uu-00@wagner.rustcorp.com.au> (raw)
In-Reply-To: Your message of "Thu, 07 Mar 2002 22:29:44 -0800." <3C885A58.4040307@zytor.com>

In message <3C885A58.4040307@zytor.com> you write:
> Okay, dumb question...
> 
> What can this do that shared memory + existing semaphores can't do?
> 
> 	-hpa

Ignoring speed issues and the fundamentally horrible interface of SysV
semaphores, there are two main issues:

1) There's a limit on the number of SysV semaphores you can have.
2) Instead of one object to deal with (ie. a memory region), you now
   have two, with different lifetimes.

Hope that clarifies,
Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.

  reply	other threads:[~2002-03-08  7:06 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-03-07 12:11 furwocks: Fast Userspace Read/Write Locks Rusty Russell
2002-03-07 12:40 ` Peter Wächtler
2002-03-07 14:41   ` Hubertus Franke
2002-03-07 12:50 ` Arjan van de Ven
2002-03-07 15:33   ` Hubertus Franke
2002-03-07 15:42     ` Arjan van de Ven
2002-03-07 19:11       ` Hubertus Franke
2002-03-07 20:17         ` H. Peter Anvin
2002-03-08  6:27           ` Rusty Russell
2002-03-08  6:29             ` H. Peter Anvin
2002-03-08  7:09               ` Rusty Russell [this message]
2002-03-08 19:32             ` Jamie Lokier
2002-03-08  1:22     ` Rusty Russell
2002-03-08  3:26       ` H. Peter Anvin
2002-03-08  9:21       ` Peter Wächtler
2002-03-08 18:13         ` Hubertus Franke
2002-03-09  4:50         ` Rusty Russell
2002-03-11 18:47           ` Hubertus Franke
2002-03-07 15:28 ` Hubertus Franke

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