From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 1 Oct 2002 15:50:46 -0700 From: "Kingsley G. Morse Jr." Subject: Faster TCP wakeups Message-ID: <20021001155046.A23683@debian1.loaner.com> Reply-To: "Kingsley G. Morse Jr." Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: owner-linux-mm@kvack.org Return-Path: To: akpm@zip.com.au Cc: andrea@suse.de, linux-mm@kvack.org List-ID: Hail Andrew, I don't think we've met, but my name is Kingsley G. Morse Jr. and first of all, I'd like to thank you for improving the Linux kernel. I'm benchmarking it. I noticed in Kernel Traffic #186 that you've converted TCP/IPV4 over to use faster wakeups. This intrigues me, because I suspect TCP code is degrading my computer's performance over time, and perhaps other peoples' too. My benchmarking found that after being up for 10 days, my computer's slowness is MOST correlated to how often slab pages are allocated for TCP open requests. (see "cat /proc/slabinfo") In other words, the more often slab pages are allocated for tcp open requests, the slower my computer gets. The correlation coefficient is 0.62, which is on a scale of -1 to 1. I believe it's noteworthy that 0.62 is higher than any of the hundreds of other memory measures that I've statistically analyzed. It's also higher after 10 days of uptime. Just after booting, it's only 0.11. I suspect a TCP bug is causing fragmentation or some other problem that gets worse over time. Cheers, Kingsley PS: My computer has 64 MB or RAM 1 GB of swap 200 MHZ Pentium Pro 2.4.19-aa -- 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/