From owner-freebsd-current@FreeBSD.ORG Sat Dec 26 17:56:51 2009 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 98BE31065692 for ; Sat, 26 Dec 2009 17:56:51 +0000 (UTC) (envelope-from bf1783@googlemail.com) Received: from mail-ew0-f226.google.com (mail-ew0-f226.google.com [209.85.219.226]) by mx1.freebsd.org (Postfix) with ESMTP id 303758FC16 for ; Sat, 26 Dec 2009 17:56:50 +0000 (UTC) Received: by ewy26 with SMTP id 26so6202153ewy.3 for ; Sat, 26 Dec 2009 09:56:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:date:message-id:subject :from:to:cc:content-type; bh=STK2iRSSj8PzkhL928sHTIq4TwsTBndvif7xPo0qG0g=; b=xD4SKx3qZihTlvjgK9SqrsYQozFIGwJD1UkfFI/d0Th58AmdnLSyQkYNY/t/Yz7l/H VA+zRHy8EY/wkGtgvy13gJnJPlhKhR9quGomddOZFN/YJ1P5O4c3AaSldoY8CexpXXF8 dshslZ9RC+NO2BnDVfJ9+YrEUgC0pNK5JqbnM= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:cc:content-type; b=Y/ly/DShRBPcxWHyrCfLxYqzzygJ/sLrMBRYexz+k4p4eewpccHmXW4vdhbPDrS4jt iDDPiV7KbOS8bQX16EOoNGOkAUFBTFkBq+vAMB+0LWD9H05+IyG78lgOLwOOvcy+NGEX r8YXDCtIJETGk1AMmLIy1NVqaUfISDrJdXL+s= MIME-Version: 1.0 Received: by 10.216.89.135 with SMTP id c7mr4935624wef.62.1261850209980; Sat, 26 Dec 2009 09:56:49 -0800 (PST) Date: Sat, 26 Dec 2009 12:56:49 -0500 Message-ID: From: "b. f." To: Luigi Rizzo Content-Type: text/plain; charset=ISO-8859-1 Cc: freebsd-current@FreeBSD.org Subject: Re: select() returning early from timeouts ? (on qemu, HEAD and RELENG_8) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 26 Dec 2009 17:56:51 -0000 >I was wondering if someone can try the above on real hardware >and let me know. 9-CURRENT amd64 r r200984M legacy usb support off in bios >From loader.conf: kern.hz="100" hint.apic.0.clock="0" hint.atrtc.0.clock="0" >From sysctl.conf: kern.timecounter.hardware=i8254 sysctl shows: kern.clockrate: { hz = 100, tick = 10000, profhz = 100, stathz = 100 } kern.timecounter.tick: 1 kern.timecounter.choice: TSC(800) HPET(900) ACPI-fast(1000) i8254(0) dummy(-1000000) kern.timecounter.hardware: i8254 kern.timecounter.stepwarnings: 0 kern.timecounter.tc.i8254.mask: 4294967295 kern.timecounter.tc.i8254.counter: 1239934843 kern.timecounter.tc.i8254.frequency: 1193182 kern.timecounter.tc.i8254.quality: 0 kern.timecounter.tc.ACPI-fast.mask: 16777215 kern.timecounter.tc.ACPI-fast.counter: 8027521 kern.timecounter.tc.ACPI-fast.frequency: 3579545 kern.timecounter.tc.ACPI-fast.quality: 1000 kern.timecounter.tc.HPET.mask: 4294967295 kern.timecounter.tc.HPET.counter: 519307291 kern.timecounter.tc.HPET.frequency: 25000000 kern.timecounter.tc.HPET.quality: 900 kern.timecounter.tc.TSC.mask: 4294967295 kern.timecounter.tc.TSC.counter: 4274176162 kern.timecounter.tc.TSC.frequency: 800000000 kern.timecounter.tc.TSC.quality: 800 kern.timecounter.invariant_tsc: 0 kern.hz: 100 #time ping -c 21 localhost PING localhost... (127.0.0.1): 56 data bytes 64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.080 ms 64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.037 ms 64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.033 ms 64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.036 ms 64 bytes from 127.0.0.1: icmp_seq=4 ttl=64 time=0.032 ms 64 bytes from 127.0.0.1: icmp_seq=5 ttl=64 time=0.033 ms 64 bytes from 127.0.0.1: icmp_seq=6 ttl=64 time=0.039 ms 64 bytes from 127.0.0.1: icmp_seq=7 ttl=64 time=0.033 ms 64 bytes from 127.0.0.1: icmp_seq=8 ttl=64 time=0.072 ms 64 bytes from 127.0.0.1: icmp_seq=9 ttl=64 time=0.034 ms 64 bytes from 127.0.0.1: icmp_seq=10 ttl=64 time=0.034 ms 64 bytes from 127.0.0.1: icmp_seq=11 ttl=64 time=0.032 ms 64 bytes from 127.0.0.1: icmp_seq=12 ttl=64 time=0.041 ms 64 bytes from 127.0.0.1: icmp_seq=13 ttl=64 time=0.038 ms 64 bytes from 127.0.0.1: icmp_seq=14 ttl=64 time=0.033 ms 64 bytes from 127.0.0.1: icmp_seq=15 ttl=64 time=0.033 ms 64 bytes from 127.0.0.1: icmp_seq=16 ttl=64 time=0.032 ms 64 bytes from 127.0.0.1: icmp_seq=17 ttl=64 time=0.032 ms 64 bytes from 127.0.0.1: icmp_seq=18 ttl=64 time=0.032 ms 64 bytes from 127.0.0.1: icmp_seq=19 ttl=64 time=0.033 ms 64 bytes from 127.0.0.1: icmp_seq=20 ttl=64 time=0.069 ms --- localhost... ping statistics --- 21 packets transmitted, 21 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 0.032/0.040/0.080/0.014 ms real 0m20.198s user 0m0.000s sys 0m0.002s Apart from the possible emulation complications, the i8254 calibration code has been removed, and there was some discussions about i8254 problems back when you outlined your callout change proposal... Regards, b.