Date: Mon, 13 Nov 1995 04:17:27 +1100 From: Bruce Evans <bde@zeta.org.au> To: current@freebsd.org, imb@scgt.oz.au Subject: Re: calcru: negative time: %qd usec Message-ID: <199511121717.EAA17041@godzilla.zeta.org.au>
next in thread | raw e-mail | index | archive | help
>What causes "calcru: negative time: %qd usec" to appear all over the >console. I'm running -current sup'd today on a 486DX2/66. I know it comes It is caused by the clock running backwards. `%qd' is supposed to show how much the clock is wrong by, but the kernel printf doesn't support quads. >from ../sys/kern/microtime.as but did something change to break it ? The message comes from kern_resource.c. The bogus time [difference] probably comes from a bug in microtime(). Perhaps the 8254 counter is not being read correctly, or a time daemon is fiddling with the clock. You can delete the message without losing much (first change it to print the value as 2 longs). The negative times are now replaced by 0. In 2.0.5R, a negative time of -1 usec gave a resource usage of 2^32-1 usec. I wonder if this was responsible for the "freezes". The scheduler should give a very low priority to a process that has consumed 2^32-1 usec of time resources in a few usec of real time :-). Bruce
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199511121717.EAA17041>