From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 16 Aug 2004 16:29:42 -0300 From: Marcelo Tosatti Subject: use for page_state accounting fields Message-ID: <20040816192941.GB21238@logos.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-linux-mm@kvack.org Return-Path: To: akpm@osdl.org Cc: linux-mm@kvack.org List-ID: Hi Andrew, I suppose you wrote the page_state per-CPU statistics structure. There are some fields, for instance pgactivate/pgdeactivate, that do not seem to be used anywhere. Sure, they are useful for statistics, but no place in the kernel exports them to userspace AFAICS. unsigned long pgactivate; /* pages moved inactive->active */ unsigned long pgdeactivate; /* pages moved active->inactive */ Counting them is somewhat expensive I believe (need to disable IRQ), based on the assumption that these days any cycle is a loss. So, from my POV we should a) export them to userspace b) surround them by CONFIG_DEBUG_MMSTATS or something similar Tell me I'm wrong. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: aart@kvack.org