From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: To: 9fans@9fans.net From: Richard Miller <9fans@hamnavoe.com> Date: Tue, 6 Mar 2012 10:39:51 +0000 In-Reply-To: <2579b8.491be6b4.43V1.mx@tumtum.plumbweb.net> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Subject: Re: [9fans] usb slowness Topicbox-Message-UUID: 66bfb4cc-ead7-11e9-9d60-3106f5b1d025 > if i force polling, it's a little faster: 0.01u 0.45s 17.70r That's interesting - it shouldn't make a difference unless there's something wrong with the controller or the driver. What did you do to force polling? > holding a second, time wouldn't show interrupt-handling time, correct? Yes, I think you're right - system cputime will only be incremented for a running process. But you can watch the last column of /dev/sysstat (or use 'stats -I') to see the percentage of time spent in interrupt handlers. > load remains fairly low during both, but system calls and context > switches are high. How about number of interrupts? Erik's theory was that you were getting too many of these.