Messages in this thread | | | Date | Wed, 22 Dec 2004 11:06:27 -0500 | From | "John W. Linville" <> | Subject | Re: zero copy issue while receiving the data (counter part of sendfil e) |
| |
On Wed, Dec 22, 2004 at 04:50:05PM +0100, Martijn van Oosterhout wrote:
> Generally, reading from memory takes time because the CPU has to wait, > writing is free since it can be deferred in the cache (in theory > indefinitly) until there's free cycle.
I'm not sure I'd call that "free" -- executing the instructions for the write has a non-zero cost.
Still, it is significantly cheaper than the read...
John -- John W. Linville linville@tuxdriver.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |